She was, for a long time, untouched by the corruption of nu-MLP. She sucked in her first film and the second film redeemed her as a character, person, and concept. She was kind, thoughtful, confident, supportive, she's everything a good waifu should be and while I still love Twilight and Pinkie, I'll admit I'd love a wife like Sunset.
As MLP's writing quality declined and everypony's waifu got flanderized so bad the dumb ones got new shit waifus like memehorse I or memehorse II or memehorse III: Rocks Edition, Sunset stayed likable, even when her whole world got fucked over by sci-twi removing its ability to be its own thing AND the new shitty specials shoehorning glimmyglam in there to please the glimmerniggers.
It's funny, the writers thought if they put Glimmer and Shimmer together, we'd "Realize" we forgave Shimmer but not Glimmer. Instead, it just reminded us that where Shimmer fought to earn redemption, Poochie had forgiveness handed to her.