I believe copyright is complete rubbish; it's just a legal extension of a sense of entitlement.
Since I believe copyright is rubbish, I must believe that all that is based on it is rubbish, including the GPL. Therefore, I won't use it.
The MIT and BSD licenses are good "interface adapters" between creators who believe copyright is rubbish, and the practical world with its legal framework which insists that there must be copyright.
Stallman also basically believes copyright is rubbish, but he used it to forge the "copyleft" which exploits it for an agenda.
My view is that if you disagree with it, don't wield it.
(Comment under this same submission.)
The BSD is a great way for those same companies to get your $100... and ask for another $500.
But if you can make your stuff work with no abstract legal entities getting involved, then sure, BSD or CC0 are the best.
Would I feel miffed if someone stole my biggest open source project?Maybe. Would that make me wish I had GPLed it? No.
I also have no idea what the percentages are on influence but my personally belief is MIT/BSD breed more open source than GPL. GPL attempts to breed open source by force. MIT/BSD by kindness. I'd like to think MIT/BSD does better because of that. It makes it easy for people to contribute and or fork and share and not worry their contributions can't be used in their own non open projects. You might see that as less open but I see it as more because their contributions wouldn't exist otherwise.
I think LLVM and all the zillions of things that are being spawned from it are a good example. If it was GPLed I doubt most of those projects would exist.