Same to be said about healers though, when healers die, the dps die and usually tanks then die because casts are getting off.
Now you are moving benchposts, you have gotten better at the game, but for the masses no. The devs already squished the keys for people like you (a 10 is a old +20) and blizzard themselves deemed that +10 keys will open route for mythic track gear (which is needed in higher keys.)
Its artifical game extension, just like how they did horrific visons, how they do mythic raid lockouts. Anything to play engagement metrics
The other issue is that DPS can do 40+ million dmg in certain pulls, and tanks dont have the raw dmg to hold it. Tanks usually generated 400-500% of their dmg as threat. So if the tank isnt doing 10m dps when you are doing 40 million? Its likely that you will rip. (Grossly simplified ofc, but threat goes far deeper than “just wait”)