In this instance the PR that was merged was from 6 years ago and was clear https://github.com/pedronauck/reworm/pull/28. Looks to me like a force push overwrote the commit that now exists in history since it was done 6y later.
Use the lessons learned from those before us in less heterogeneous days, aka inspect the binaries you're going to call out to for fitness. Things like "check if grep is gnu or bsd" or "check if sl is sapling or steamlocomotive".
I've done that a bit to deal with macos crippled bash for example.
True, but I imagined fetching every file with wget or equivalent and then just using it locally. Doesn't work anyway because the data is not all there.
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