> I'm just not sure who "the others" are that I shouldn't slight by omission.

https://morph.zone/modules/newbb_plus/viewtopic.php?forum=3&topic_id=11372&start=22 ;-)

> if MUI for AmigaOS is not supposed to be called MUI4, why IS it?

I guess because it is based on 2006 MUI4 source code and the maintainers think it is supposed to be called MUI4 ;-)