Idk if this has been mentioned by anyone yet, but you mustn't consider the new DPS classes as just "DPS." Remember that, within DPS roles, there are both melee and ranged DPS, and the later are divided between physical and casters.

There hadn't been a melee DPS since the introduction of Ninja in 2.4, and there hadn't been a caster since the literal release of the game. This is almost three years of wait time for casters!

I know this might not mean much for tanks or healers, but there are people that prefer certain playstyles to their jobs, so getting a new caster and a new melee DPS is giving a new toy for people who hadn't gotten one for far longer than us tanks and healers did