mostly because a huge population of this games active player base are pvp players (most classic players are) and blizzard GUTTED premades, destroying the pvp community. Then they took it 5 steps farther and made hunters, Shamans, spriests, and boomkins pvp GODS, nothing even comes close. then they refused to fix the problem, buffed these classes further, gave them insane runes, and then buffed them again.
now you have a heavily skewed ranged only meta because outside of shamans and hunters, melee players cant even get to their target without 10 dots, 3 fears, 5 stuns, and a 2.7k mage crit. making melee players just say “lol no thanks, i may as well go play retail, atleast melee classes are up to speed there”
Blizzard has heavily buffed all ranged and hybrid classes to be the gods of SoD, playing SoD pvp is next to impossible unless youre a ranged character, or an enh shaman.
to top it all off, shamans are so insanely overbuffed right now that they can easily destroy any class in the game in seconds, heal up to full, then do it again. making AB/WSG alliance teams walk away from the game.