Indeed they are compatible. However HTTPS is often unnecessary, particularly in a smaller organisation, but browsers mandate significant unnecessary complexity there. In that sense, brwosers are not suited to this use in those scenarios.

If only browsers could understand something besides HTTPS. Somebody should invent something called HTTP that is like HTTPS without certificates.

I really don't see many scenarios where HTTPS isn't needed for at least some internal services.

And it is even more trivial in a small organization to install a Trusted Root for internally signed certificates on their handful of machines. Laziness isn’t a browser issue.