Yeah, we should give a shout-out to the octobus folks for making heptapod, a Gitlab fork bringing support for mercurial repos. That brings at least one mainstream hosting option for hg repos.
Absolutely. I guess most of us have a bunch of repos which are personal anyway which are just as easily "hosted" as Mercurial repos. I.e. if I have ssh access to a machine, "hosting" a remote Mercurial repo with
hg init
git init --bare
I'm certainly in that camp; and it pains me every time I have to use the hggit extension to convert a mercurial repo to git in order to work with everyone else...