for some reason a lot of emudevs are very hostile to the whole idea of forking. mame also famously hates retroarch for it, as well as inolen from redream and skmp from reicast/nullcast, probably more.

this isn't even the first project that an emudev has directly relicensed or even shut down their entire emulator for over a retroarch fork, which is usually done in the first place due to maintenance problems with the original emudev.

as others have said, the whole scene just seems to attract the kind of genius that too often steps over that fine line. out of the probably couple dozen emudevs I know, the vast majority have explicitly stated themselves that they suffer from severe mental health issues.