Legion only looked good since it was after Warlords which the only thing to be kept was its “item level scaling system”, also it looks good because bfa is disgusting, legion was a subpar expansion gameplay wise.
The golden era of wotlk / Cata / mop (while still stained by ridiculous crap like s5 dks, s9 mmr bug, s10/11 pve fiesta, s12 war and stampede bugs) quality gameplay will never be matched again, even if something looks “ok” now it will still be way under the high standards established back then, even if once again it wasn’t perfect, it was FUN
they just made their game like overwatch, hard counters and no fun in facing a counter; back in the days you’d see ppl dueling 24/7 against their “counter” to learn and improve, now basically you can’t because the game isn’t designed like this anymore. Thing is, you can’t switch classes like toons in a game like overwatch so this is how you end up with a boring game