I think so, but, only if you differentiate in the privacy angle (think Proton vs GMail) and this is similar to how most enterprise GIT offerings work, too. The risk is GitHub offering to existing orgs who are already on Office 365 a self-hosted version (I think they already do). So, this business model will fail in the SWOT analysis itself. Still, there might be some looking to exit MS office ecosystem, it might make more sense for them.