I'd like to see Canon's apparently reverse-engineered system become the de facto standard so a camera can communicate intelligently with studio lights, meters, the whole shooting match.
I don't see any reason why Yongnuo wouldn't want to release triggers for rt older Speedlites and studio flashes, though it's duplicating their non-rt radio trigger/flash line, but if the demand is there...
What still puzzles me is Canon, they must have seen this coming, or someone just got fired for not properly encrypting their rt protocol. So I wouldn't exclude the possibility that something new is in the queue like the 430ex2 successor once the Yongnuo flash clones are actually on the market in sufficient quantities.
The other possibility might be that Canon indeed doesn't care which might be backed by the fact that the rt protocol is not very innovative other than the group mode which fixes the completely outdated/quirky ratio system - no second curtain remote, no remote zoom.