There are, broadly, two types of FOSS licenses when it relates to commercial usage of the code - let's say the GPL-type and the BSD-type. The first is, broadly, restrictive about commercial usage (by usage I also mean modification and redistribution, as well as creating derived works, etc.) of the code under the license, and the second is much more permissive.
As I understand, the idea behind GPL-type licenses is to encourage people to abandon the proprietary software model and instead convert to the FOSS code, and the license is the instrument to entice them to do so - i.e. "you can use this nice software, but only if you agree to come to our camp and play by our rules".
What I want to ask is - was this strategy successful so far? I.e. are there any major achievements in the form of some big project going from closed to open because of GPL or some software being developed in the open only because GPL made it so? How big is the impact of this strategy - compared, say, to the world where everybody would have BSD-type licenses or release all open-source code under public domain?
Note that I am not asking if FOSS model is successful - this is beyond question. What I am asking is if the specific way of enticing people to convert from proprietary to FOSS used by GPL-type and not used by BSD-type licenses was successful. I also don't ask about the merits of GPL itself as the license - just about the fact of its effectiveness.
