As long as projects need to distribute software that is not code, there will be projects for whom a Github-only solution is inadequate. This opens the door to competitors who are willing to offer "Github, plus that one feature that you really need but that Github doesn't think that you do".
"[...] part of our ongoing effort to keep GitHub focused on building software [...]"
So I suppose that Github Pages and project wikis will soon be gone as well?
All I'm asking is for you to be honest, Github. Just come out and say that the feature was a pain in the ass to support and a looming legal liability.