Where I work we're hosting our own gitlab instance and the previous company I worked for hosted their own Bitbucket. For most developers I know it's either a self hosted git platform instance or Github enterprise.

I've asked around in my circles, because I am genuinely interested: Everyone not working in startup space IS hosting their own instances.

Hell, even I do it.

Even my faculty, which otherwise licks Microsoft’s boots at all opportunities, uses self-hosted GitLab.