I think the reason why nobody has bothered with digital amps in context of power amps is because you can only 2/3rds of of the power from a digital amp..
I don't know that this statement is accurate. From what I've researched, there can be digital amps that can handle higher power ratings. As some examples, there are the two Axiom amps (like
this one) several Rotel amps (like
this one) that can do 200W and more.