I'd have guessed mostly countries which were late to the v4 distribution to be in there - but apart from India and Malaysia everyone should have enough v4.
I guess the long delays combined with changes in v4 usage by cloud hosters gobbling up any v4 addresses while also not properly doing v6 yet changed the situation also in countries which should have had more or less sufficient v4 reserves.
It's still shocking how long it is taking. I stopped doing IPv6 workshops back in 2006 as I got tired of waiting - and had a few years of no v6 usage myself after sixxs shut down. I only could get proper v6 at home last year.
Somebody is pretty salty for no good reason. The maintainers own patch is nicer code than the suggested patch - and the change is small enough that there just isn't anything available to guide the reporter to a better solution without wasting everyone's time.
I'd probably have added a thanks for debugging effort into the commit message myself - but "please accept my patch because I want to have code in the kernel" is a very stupid thing to say, and the maintainer offering a suitable problem to fix is more than I'd have done in that situation.