Maybe there could be another reason why people choose MIT to begin with:
When you start a new repo on github it makes suggestions which license to use, and I bet many people can't be arsed to think about it and just accept what they're offered. [My memory is a little patchy since I very rarely use github anymore, but I definitely remember something like this.] And maybe github tends to suggest MIT.
That said, please undestand that many, many git platforms exist and there is no reason at all to choose one of the two that actually have the word git in them.