DI specifically said he didn't want to commit to updating all HX amps because they'd like to do new stuff too. And at least one HX amp - the Trainwreck Express - isn't even available to them anymore to be updated.
For effects, I think people will largely want, different effects. An updated "Plateaux reverb" wouldn't really be worth the trouble, although I do think they would do themselves a favor by exposing more parameters to make their reverbs and delays even more tweakable.