Why are you telling me this, I already knew all of that and I agree that WoW got shit after TBC.
I myself don't really play this game for PVP or endgame content, I just play different classes for the sake of questing to max level and tell myself I beat the game. I'm just arguing how I'd rather play on private servers because I disagree with paying taxes over a videogame. Sure it's much emptier and some of the quests don't even work, but considering it's pretty much an online singleplayer experience for me anyway, I don't mind.
I did play retail TBC back in the day on a friend's account though. For some reason I didn't find the charm in this game with my first character for 20+ levels, then came back a month later, made a new char and instantly understood the magic of it all.
I've also played Legion on private servers and it's a mixed bag for me, I like how mounts can be acquired much earlier and how flying is implemented, but you gain wayyy too much XP for my taste. In TBC you had to stick to an area for a few days before your char grew enough to explore to the next area, now you can pretty much grind one area after another in a matter of hours, it takes away a large sense of achievement and I don't like that.