IIRC TRP are doing a set of road caliper brakes with the hydro gubbins in the stem, they use that bellows thing rather than pistons as well.
I think Shimano have instigated the push for disks with the UCI for cross, can't see it being massive in cross unless there's a huge reduction in weight of disk brakes and an awful lot of rame development.
Conversely there's a huge market for commuters, tourers and everyone else not going eye balls out for an hour.
I know people moan about cantilevers on cross bikes but I guess the reason they've remained popular at the top level for year is that they're light, also there's not a huge amount of real braking that seems to go on in top level racing a bit of slowing yes, but actual hard braking not a lot.