I don't know, I've worked with tiny startups and bigger companies like Red Hat, and huge banks, and GSuite is very widely used. The biggest corps don't seem to use it, but I definitely don't think it's only used in a small insular bubble

I don't know a single person in the company I work for that use MS Office or has done the last three or so years.

Supposedly you can get a license if you need it, but I don't know anyone who need it or even complain about it.

Everything goes in Confluence (or.md files in repos) or something similar these days, doesn't it?

Most other startups I know use GSuite.

I have never heard of a college course about Microsoft Office at a university in the US. And I went to college in early to mid 2000s.