I partly blame the angle for the backlash against Nia.
I know Alexa Bliss is hilarious and everything, but those segments were like...too good. She got cheered for them, instead of creating any sympathy for Nia. And turned the idea of bullying itself into a jokey punchline for the heel, instead of a real thing like it was pre-Mania. Like, Alexa was saying "you're a bully!" to her during the match. So you turn the idea into a joke like that, and afterwards try to give her this heartfelt moment...the tone was all wrong. If they really wanted to do it, tonally that promo would have fit better after Mania. Here it didn't fit at all because Alexa used the word to get over as a hilarious heel in the build. Regardless of Nia's delivery.
Also for the fact that the match itself did NOT sell the idea of Nia getting righteous babyface revenge against a bully at all. She got beat up for a lot of it and seemed to escape with one big move, rather than teach Alexa a lesson. It was just all wrong.