Ladder and tourny are different.
Tourny realm has access to full renown trees, BiS max ilvl gear/enchants/gem slots and stuff like PVE trinkets at mythic ilvl if they choose too.
A mage might instant gib you on live but on tourny they won’t, not with those healthpools.
Those same reasons might allow locks some gameplay and spotlight on tourny since they will be much sturdier vs live.
Also your experience vs fire mages and combust is not the same as AWC either.
Do you really think trill at 3200CR is getting farmed by fire mages at #1 on ladder? Or even remotely bothered by their existence?