This is about the only way that it's going to overcome the need for an analog signal to be sent, and often stored (as this is cheap and easy and fast). But to do it is equivalent to making a closed loop servo active loudspeaker with a DAC on board, with all tailoring of responses meticulously designed for that hardware, as a single and EXPENSIVE unit. So far as I know, this has not yet been invented and sold commercially, even to top studios. While there are esoteric projects that can be found via Google, perhaps, they're rare, last one I saw was huge and cost the kind of money people buy large houses with.
People might still be discussing how to make a digital signal go to a specialised scan renderer decades from now but what's the point? More speed to let you fill in blocks of colour within a frame? To scan more lines per second? Right now you can do this with a video projector, or a few laser projectors. So long as you move a mass that scans a single beam, that can only point at one spot at a time, it makes no sense to prevent the analog signal being open to all to access it their own way. If top bods of the ILDA are seriously suggesting hardware that prevents this, they're more likely to fuel continued speculation that they're trying to create further exclusion than anythign else.
It doesn't matter how you work out what the beam will draw, it's still got to draw it. The only thing the scan amp should be doing is to do this faithfully, except where such instruction endangers the scanners, in which case all it needs to do is impose a voltage and slew rate restriction so the scanners don't take the flak.
EDIT: keeperx, precisely so.