Yoshi-P: "If you want more engaging content, go play Ultimate"

[Aravell]

But having a healer suddenly do dps of a tank because of it makes zero sense and would result in them becoming something they aren't intended to be.

A healer doing the dps of a tank has always been the case. WHM has always been roughly on par with the tanks, SCH is about 10-15% behind the tanks and AST is about 30% behind, with SGE being roughly where WHM is. So it's not exactly something they aren't intended to be.