Cautious support for this from me, fwiw...
Provided the balance is done well enough between lowering player power and mob/dungeon power (need to think about stuff like trap DCs and damage, etc.), this should be a positive development.
As ever, the proof of the pudding will be in the eating, but in principle I'm in favour of reversing power creep.
A bit of patience will be required from the player community I think, as I doubt everything will work out first time without anomalies.