x264 offers a commercial licensing program for this reason.

No, they released x264 under GPL from the very beginning, the commercial licencing came much later and the reason they offer this is because it is how they (the x264 authors) make money on x264, namely by offering proprietary licences for companies who wants to use x264 in proprietary projects.

And there's a new x265 project (not by the same authors) which is using the exact same model, which is that they release it under GPL and will also be selling proprietary licences.

a) they only offered that later on b) they offer it so that people who don't like the GPL have an option, which is a fairly standard thing for projects that aren't worried about patents to do, not because the GPL is incompatible with x264

I didn't mean to imply it was the only reason for pursuing a dual-licensing model, but when I spoke to DS about it many years ago (before x264licensing existed) he recognized that it was a potentially serious problem.

He certainly recognized that patents is a potential problem, x264 is a implementation of patented technology, however that problem is not tied to the licence no matter what jwr is trying to spin.

And patents had nothing to do with them offering a dual-licence model, it was in order to be able to make money from their work when companies wanted to use x264 in a proprietary fashion (GPL is not compatible with proprietary), and from what I understand they have been doing great business this way.