Isn't that going a bit overboard in an educational setting, though? Seems to me like it'd be like showing up for a drivers ed class and spending the first semester learning about the history of internal combustion engines.

Sometimes it's best to start with something that transparently "just works", make the students aware of other options like gitlab, and let them explore those if they wish.

Depends on what the end goal of the education system is: to make you a driver/chauffeur or to make you someone who is going to design the car of the future.

How to stage and sequence the exposure to the details is indeed important. I am not advocating exposure to the details right away, but the option has to be available at a reasonable price (be it in money, or in time).

There is also the "teach a person to fish" thing, rather than handing him/her a fish. Although many are in the business of handing out fishes, stale ones too.

That assumes that everyone who was using GitHub for hosting their classwork is engineer capable of hosting their own Git server. What if they are working on frontend HTML/CSS things? or just learning Python? There are lots of valid uses for version control that don't mean you already have the ability to even try to host your own VCS.

No one argues that you need to have people host their own web server to start learning how to write Javascript. In fact, most would argue against hosting your own that early on. It's not beneficial, and more likely to end up tangential annoyances than solving the problems that matter for the person's skill level.

Just because someone teaches you a different part of the stack first doesn't mean they are handing out fish...

Students can maintain a local git repo and just push their results to github. In fact, they must, that's how Git works!