everything has been good at one point or another but ele enh has spent long stretches are very sub par… ret has historically been bad or oppressively good… a giant stretch in the middle of wows life warrior and hunter were pretty average but both have been really good over the last 2-3 years but boy was legion and bfa and most of wod a really unfun time to play war… my enjoyment of war never really recovered after that i played barely any in SL and dont play it now.
spec design back in the day they leaned into a pvp spec and pve specs… frost mage, sub rog, arms, marks to name a few were they would just not do well on raid bosses but their toolkit was very solid for pvp engagements… aside from certain specs just doing bonkers damage those were pretty consistently the "pvp specs " the class reworks kinda shook things up in legion tho. since most mage or warrior or rog specs basically do the same thing with difference spell effects its really who just does the most damage gets played…
raisin is correct tho outlaw and arcane are normally pretty terrible but i dont think assa is though its normally painfully average or overtuned which is were dk seems to have fallen since legion also