Forcing people to contribute sounds like a great idea, until nobody wants to be forced and everybody prefers the other project that doesn't force them, and then they all go ahead and contribute to that other project anyway because they want to, not because they were forced to (in large part because the practical benefits of getting your changes into the upstream vastly outstrip any theoretical "my code is better" fantasies).
Faster adoption of non-GPL projects leads to faster growth of those projects in the form of more contributions as well. Other than a group of mostly quite old GPL projects the momentum and activity and success is clearly with more MIT-like licenses than GPL-like licenses, again in large part because the benefits to you of getting your patches into the upstream proves to be a powerful motivator that is not also a demotivator the way the threat of being forced to contribute is.
Yes, one can point out a newish successful GPL project here or there and a couple of pro-GPL ecosystems but the vast majority of recently successful project starters are using MIT-ish licenses for good reasons.