The practical answer for right now is that I don't want software screen capture, but it also does not do any of the things I wanted to be able to do by having remote inputs directed to the hardware rather than simulated in software. Namely it requires software installation on the server, which means OS support becomes a thing, you can't use it in BIOS/firmware, etc.
Sunshine works on linux and windows, screen capture uses parts of the gpu meant to do that as result you get lower latency than separate capture and encode.