Same here, Princess Celestia is not a democratically elected Ruler, but she is not a fascist, She does not impose martial law, if something does not go her way, she would prefer to discuss it with her subjects politely instead of assuming arrogance and being condescending. I know she banished Nightmare Moon to the moon for a thousand years, but she was a threat, eternal night has lethal implications for an ecosystem IMO. if excluding the comics due to not considering them canon, then bullying from Celestia was not the reason for Luna's outbursts, a misunderstanding was, which led to the fight between them as shown in episode Princess Twilight Sparkle from season 4.
Princess Celestia also allows local government to have elected Mayors, and she allows journalism, and endorses fund raising for charities for schools, further demonstrating that she has restraint on her own authority. She could Rule with absolute power if she wanted to, but she chooses not to.
I think that was one reason why Princess Luna chose to settle her differences with her sister calmly, she realized that Princess Celestia is not a monster, bossy at times, yes, but then what sibling doesn't argue with their family from time to time? nobody agrees on absolutely everything another person does.
If I were in the fantasy world of Equestria like one of my OCs in my fan fiction, I'd have much more important things to worry about than find something to argue with Celestia about. Like learning how to fly as a Pegasi for one thing, getting an education, and learning how to avoid dangerous creatures like in Everfree Forest.