Equestria Girls didn't subvert anything. It was as trite and cliched as it could have possibly been.

Dumbing down Twilight so she could fit into her "new girl" niche? Check.
Bland male love interest? Check.
Mean girl antagonist? Check.
The student body splitting into several different cliques? Check.
Bringing them all together through song? Check.
Musical numbers accompanying the gym clean-up and clothes-shopping? Check.

The list goes on. Granted, transforming into a demon is far from typical, but that doesn't mean much when you consider that she was defeated in the most contrived way possible. And while Gary Stu may not have been a prince, he might as well have been.

I could refute this logically, by pointing that in the episode Discord pretty much outright says he hasn't completely reformed ("I'm ready to use my magic for good instead of evil--most of the time") and that this was confirmed in the season 4 premiere (Spike even says "He's reformed, but he's not that reformed").
But then I saw who uploaded this image, so instead I'll just say "welcome back, LezHuarez."