I think, rather than looking at the Source First license as something that’s “a replacement for OSI Open Source but less free” it’s more useful to see it as “a replacement for closed source commercial licenses but radically more open”.

Open source has created some really great backend software and developer tooling, but somehow it’s not great at making nice consumer-friendly client side apps. When you look at the best apps, even the ones like Chrome that use open licenses, they are created by a relatively closed group of developers funded by a for-profit company.

The Source First movement is aiming to provide a way for that kind of closed focused team to be more open with their users. I don’t imagine that many Source First projects are going to be looking for lots of community contributions, and that’s ok - the closed source apps don’t do this either and they seem to get along fine.