I don't think GitHub's situation is completely analogous to SourceForge. You're right that GitHub doesn't have a huge moat by virtue of the way git works. I think Microsoft realizes that, no one necessarily loves GitHub so much they'd not jump ship if GitHub became too user hostile.
To be clear I'm not trying to be down on GitHub here. They made a good product and a very good alternative to SourceForge. I think they just got lucky getting bought by Microsoft when they did. By 2018 I think they'd gotten to the point where their costs would have required to start chasing revenue.
To be clear I'm not trying to be down on GitHub here. They made a good product and a very good alternative to SourceForge. I think they just got lucky getting bought by Microsoft when they did. By 2018 I think they'd gotten to the point where their costs would have required to start chasing revenue.