I don’t know. Fender sells a lot of Tone Master amps, which is pretty much exactly what is being discussed here. All the people buying TM amps could buy a (insert floor modeler of your choice) and run it into a powered "FRFR" speaker or poweramp into cab, and yet they just buy a TM amp. There is something to be said for leveraging digital in a way that looks and feels more “traditional”.
And I don’t know that it’s purely cost prohibitive. If Fender can sell a TM Twin combo for $1,300, surely a Helix/Fractal head could be built for something in that ballpark, where an improved power amp, and a better chip to run all their amp modeling, could be offset by not doing a combo and eating all the extra expenses for speakers, the cab enclosure, increased shipping costs etc. I don’t see why any of these hypothetical devices would have to eclipse 2k.