Well if we are talking any dungeon shb and endwalker, ill gladly jump in with 3 dps and a tank, Since endgame is relevant.
The damage and general tankiness of players at level 80+ is far beyond what it should be, warriors especially can almost solo dungeons with their self healing and mitigation
I have soloed Delubrum reginae as a warrior, a raid that scales from 8 to 24 people. This should not be possible but unfortunately the way tanks are designed is beyond stupid.
There is a video of a group AUTO ATTACKING a normal mode raid boss to death in 6.1. (Yes it took over an hour, but that is the level of difficulty that the game is throwing at people)
And the worst thing is that i actually main healer....