Linking to a video with 2k views and then saying EVERYONE in the same sentence....you're not helping your argument at all with that.
They removed abilities that most people probably never used or rarely used. They also were trying to combat screen shotting and cooldowns in general by removing some of those as well. This is all information easily accessible from Blizz themselves. The prune was needed, some classes had upwards of 20 or more abilities that rarely ever got used. They wanted to simplify the game for newer players probably, who knows. Whether or not you agree with what they did is your opinion and I could care less.
They didn't prune away the class identities like they did with Legion though.
But it's ok, all you can say is "You didn't play back then", which is like the worst comeback ever.
Regardless though, to stay on topic. Adding any new content while gameplay is in the dumpster won't do anything for the game at all. It's boring as hell to play right now, and no amount of content will make the game suddenly fun.