I've seen a small but increasing trickle of open source projects leaving github for free(libre) alternatives lately. It's not a stampede but I'd say the exodus is on its way.

The considerations for commercial users leaving github are probably pretty different, so perhaps they'll stay.

Github, i.e. MSFT will of course adjust their offer if they would start seeing an significant exodus. They could afford being a loss leader indefinitely.

There’s also a large bunch of projects that will never leave, some of which ms have influence over. I mean, some high profile open source projects hasn’t even left source forge yet, even though it has been malware infested shithole for decades.