The real problem with WoW nowadays is that your progression feels more fake than ever. You never feel strong, you never feel like you achieved something, only your ilvl increases which only let you do the same content on a more "difficult level" with few added mechanics and bigger numbers, and even if you do those, you will be afk sitting because you can't take advantage of your hard earned gear anywhere. Everyone just feel the same, everyone is equal etc. The catchup mechanism adds to this, why bother farming things when someone can do the same in 1 week that you did for months like farming Azerite, and I don't think the current WQ, Island Expedition, Warmode, Mythic+ daily for months is so fun that it's worth subbing for. The outside world scales, gear in PvP barely matters It's a repeated cycle but in the worst way. At least in vanilla, tbc, even wotlk, your character felt unique because everyone had so many different build/gear, when you get one piece of upgrade you felt like you are better now, you felt accomplishment. You went out and you felt strong.
On a side note the different difficulties of dungeons, raids totally ruins the immersion for me. There is no such thing as a big bad enemy, who is powerful, I just do some raid finder and kill the big bad guy like Gul'Dan in 1 min taking 0 dmg. That's why raids like MC Ragnaros, Onyxia felt partly epic.