I don't think you got this right, PyQt is already available GPL licensed, and that is not acceptable for Nokia, so they moved to LGPL.
The important thing here is that, if a company wants to promote any infrastructure component, GPL is a horrible license to do that. If you release a library of even a device driver as GPL, you are imposing a very strict condition on your customers, that they have to be GPL too.
This is no way acceptable for most people, and that is why LGPL or BSD licensing is attractive in this situation.
RMS has got it wrong, actuall if RMS had got his way, GLIBC would be GPL and most of the commerical guys would have to get out of developing on Linux.