Sly

Well, what's there to really talk about the Mane Six right now? They're the main characters of the movie, they'll go on an adventure, probably save the day, etc. We know those characters and what we can probably expect from them. These new characters are unknowns we have no knowledge of, and the movie is filled with them, there's just more to discuss.

As for the Princesses being beaten and whatever, they're two beloved characters from the show that haven't even been seen in the trailers yet, that's why people are curious.

Well, probably I'm an isolated case but, you know, after the terrible treatment they got in TWABA I wouldn't give anything granted for the Mane 6 in future. Like I pointed plenty of times, the Mane 6 are still the main reason I watch this show, and after that abomination of a finale, I lost most of my hype for this series, because that was the VERY FIRST sign of the show eventually taking a direction I'm not fine with. MLP has gone throught a lot of heavy changes throught the time, but while I accepted AND loved the past changes, replacing the Mane 6 is just a FUCK NO from me.... That's why I have been so vocal about my quitting, MLP never will have the ending it deserves, Starlight Glimmer eventually becoming the new star permanently in future, and all that stuff. And that's why I'm looking forward for this Movie and I'm being so nervous about the eventual S7 finale's plot. Those might be their very last chance to shine, that's why I really want both of the productions doing justice to them. 

What's this? Actually watching the show for the main characters instead of that Glimmy thing? What treachery is this?