Oh dear, I literally just remembered that I have an MLP Forums account and decided to log back into it almost four years later. Some of you may remember me for my "Anyone else here hate Celestia?" post, which mostly got negative responses (i.e. disagreements with my point of view, which I respect and understand) as people could not relate to my experience. You see, I always assumed Celestia hate was a common thing in this fandom, however, I was disappointed to find out that this isn't really the case anymore. I am still happy to see more people appreciating Princess Luna, though, as I believe she deserves much more love than she receives within the show, so it's nice to see her become more popular than her extremely flawed sister. Some of you may be wondering, just why am I calling Celestia an extremely flawed pony? Stick with me to find out. This post is going to be a megathread on why I hate Princess Celestia and why I think you should, too.
So, first things first, Celestia is an extremely incompetent ruler who has an unhealthy and I would even argue downright abusive relationship with her mentee/student. I know that because I spent years being attached to my extremely incompetent and abusive former mentor, who actually really reminds me of Celestia. Both Celestia and my former mentor were fully grown adults who relied on teenagers who were under their guidance for emotional support and partook in exploitation of said teenagers by dumping their private issues on them. You might just think I'm projecting my insecurities and trauma onto Celestia, or even wonder "when did that even happen?", which I understand. To answer your second question, the Reflections arc.
Starting with the Reflections arc... oh boy, the Reflections arc, huh? That comic revealed just how horribly selfish Celestia is, and just how much she cares about her "beloved" sister, Luna. Shortly after poor Luna's banishment, Celestia practically replaced her sister with an alternate version of her from another universe. Talk about sisterly love, huh? I cannot imagine replacing the loved one I willingly banished away for a thousand years with an alternate version of themselves, and still make myself out to be the victim in the end. Luna even calls her out for it in the comic. "B-but think about how hard it must've been for poor Celestia!-" No. Maybe Celestia shouldn't have banished her own sister to the Moon for snapping over something Celestia herself both actively contributed (I'll get to that later) to and could've prevented. Anyway, this is only a fraction of what Celestia had done in that story arc. She continued to go through the mirror portal behind her only friend's back, and lying to said friend about it, while knowing about the damage it would've caused to her kingdom... so to those claiming that Luna's banishment to the Moon was actually a "selfless" act of defense of her kingdom and subjects against a tyrant... Celestia didn't seem to care about them that much when she needed to go through the portal for her own personal reasons. Now, you may be thinking, "but what if she had good reasons?" Well... the only reason why Celestia continued to visit Sombra's Equestria was to meet up with Sombra himself, whom she had developed feelings for. Talk about a wise and selfless ruler! And when Star Swirl found out about what his friend had been doing behind his back (after promising him not to do it) and rightfully restricted her from ever going through the portal ever again, all she did was run away, without even confronting or apologizing to her friend. And she hasn't even learned from her mistakes, as she went through the portal again even after Luna's return to Equestria, which caused the story arc's conflict to begin with. And what did she do afterwards? Sent Twilight, her teenage mentee/student, and her friends on a deadly dangerous mission to go solve the problems she herself created out of selfishness. Typical Celestia.
Also, Celestia is seen having fun with Mirror!Luna, Mirror!Sombra and Star Swirl on this page:
This doesn't look like someone who's supposed to be mourning the loss of her sister, does it now? It looks like someone who is selfishly living the dream while her actual sister is suffering alone on the Moon thanks to Celestia herself.
Anyway, Reflections arc aside, remember how I mentioned Celestia herself being responsible for the creation of Nightmare Moon? Some of you may be wondering what I mean by this. Take a look at these comic pages, all taken from the official Legends of Magic issue #1.
Celestia partakes in downright bullying of her younger sister instead of encouraging and supporting her like a good older sister would. I know sisters bicker all the time, but bickering should never transform into bullying! It is never okay to bully and degrade your sibling, no matter how much you two bicker.
Despite this, Luna still refuses to turn against her arrogant and selfish sister, proving herself worthy of compassion and trust:
Next, Celestia removed Sunset Shimmer from the position of her pupil after introducing her to a mirror she apparently wasn't ready to handle, according to this comic:
She then refused to answer any of Sunset's questions about the mirror... I mean, seriously? Why introduce your student to a magical object that she apparently "isn't ready" to handle yet, only to dismiss every question the student develops about said object? Who does that? Abusive and incompetent rulers do, that's who.
Celestia then finds Sunset researching the mirror in the library, (which I can't blame Sunset for) and what does she do? She removes Sunset from the position of her pupil and banishes her from the castle altogether, which reeks of tyranny.
And that's just the comic Celestia. The one in the show is even worse.
Celestia practically dismisses Twilight's very valid concerns in the first episode, telling her to stop dabbling in old ponies' tales... and then claims she could actually sense Nightmare Moon's return and even knew about it the whole time by the end of the episode. She then proceeds to gaslight Twilight:
Twilight Sparkle: But... you told me it was just an old pony's tale.
Princess Celestia: I told that you needed to make some friends, nothing more.
Way to go, our favorite gaslighting and gatekeeping girlboss!
She does it again the season 2 finale, "A Canterlot Wedding", where she tells Twilight that she "has a lot to think about" after the latter rightfully accuses "Cadence" of inappropriate behavior. And she doesn't even apologize for it.
She later makes Twilight a princess without her consent, introducing her to a whole lot of sudden responsibilities that poor Twilight was not even prepared for ("Magical Mystery Cure").
Celestia also invites Discord to the Grand Galloping Gala despite knowing that he was going to cause trouble for the guests (her subjects that she supposedly really cares about), all because she was bored ("Make New Friends but Keep Discord").
And speaking of Discord, she forces Twilight and her friends to redeem Discord, a dangerous villain, all by themselves, just because she's too lazy to do it herself ("Keep Calm and Flutter On").
She dismisses her sister's feelings again in "A Royal Problem" and "Between Dark and Dawn", and to an extent in "Sparkle's Seven", when she does not take Luna's suggestions for improving the castle's security into account. She accuses Luna of "never being happy" and then makes herself out to be a victim when Luna brings up her banishment. She does not acknowledge the fact that she wouldn't want Luna to never come back because she missed her, but only because she doesn't like having so much pressure put on her.
By the end of the series, Celestia decides to dump every single one of her responsibilities onto Twilight without any explanation in the middle of the day by making her the ruler of Equestria without her consent. That is abuse and exploitation, much like what my mentor did to me when I was younger, and then told me to never tell anyone what she's been telling me or else she'll accuse of me of being crazy and making things up.
And just when you think she couldn't get any worse, she turns a literal child into a statue shortly after banishing her to the Tartarus, which is Friendship is Magic's equivalent of literal Hell.
Oh, and don't forget the time she basically made Twilight a teen mom by dumping Spike onto her, again, without Twilight's consent.
To summarize this, here is a funny and truthful image I found on Derpibooru: