As it stands with the talent trees shown, dps DK is the only class that doesn’t bring anything to a group. Be it utility or a raidbuff (AMZ being capped means dps dk basically have nothing there). Every other class bring heavy cc, a raidbuff, lust etc.
With Warrior, Warlock, Monk and DH trees being the only ones left to reveal, it is highly likely they will keep their raid buffs.
Blizzard should really consider adding something to death knights to actually make them useful in a raid environment. In my opinion horn of winter should be reverted to the buff it used to be. Just anything to make dk a more appealing class for Dragonflight