> The problem is that Linus is staunchly against the GPLv3
No he isn't. He is unable to relicense the kernel. Whenever he's interviewed on the subject it is always in relation to kernel development. He doesn't control the copyright on the entire codebase and there are too many contributors, some dead, for anyone to get copyright assignment sorted out.
You are right that he can't unilaterally relicense the kernel and that it will likely never happen, but Linus is in fact against the GPLv3, see debconf 14 Q&A: https://youtu.be/5PmHRSeA2c8?t=2840
No he isn't. He is unable to relicense the kernel. Whenever he's interviewed on the subject it is always in relation to kernel development. He doesn't control the copyright on the entire codebase and there are too many contributors, some dead, for anyone to get copyright assignment sorted out.