Not so long ago, a bet was made that computer printers could be combined and made to add scan, copy, and fax functions. Don't know if anyone or any organization collected on that bet, but it's pretty obvious that we 'won' the benefits of it. That combination is pretty much the default now...
I don't have any doubts that class D will eventually match all existing classes in performance, even in the high power versions. This will take awhile yet...all advances generally do. These advances are usually driven by demand, the typical market forces that make up our civilization...whether we like that or not is more or less moot.
You want the class D of your dreams? Vote with your wallet. Buy what you perceive is the best of the current litter Now and start driving the technology of the future. That's what's drove the market to where it is now and it's still on the move.
Stop whining and wishing...get out, up, and help push.