it is a feature which allows, for example, to work simultaneously on several releases, patches, hot fixes, etc. Once better alternative emerges we'll jump the git ship as we did before when we jumped onto the git ship.
>the repository separate from the data
that was a feature of a bunch of source controls and a reason among others why they lost to git.
>it forces you to
that is another reason why source controls lose to git as git isn't forcing some narrow way of doing things upon you.
I don't deny of course that for some people/teams/projects other source controls work better as you comment illustrates. I'm just saying why git won and keeps the majority of situations.