This is a case where a difference in degree makes a difference in kind. Some of these haven't been sold for over 10 years and no one knows who still has one or

This is a case where a difference in degree makes a difference in kind. Some of these haven't been sold for over 10 years and no one knows who still has one or where to get a compiler for them. Some of them are only a few years old, but have never run an upstream linux kernel (they always ran their original hacked-up/ported kernel), and again you can't find a C compiler from the last 5 years that supports them. Linux does not drop support for architectures lightly, it was hanging on to most of these for years when they were clearly un-used un-tested zombies. And, FWIW, sound-blaster sound cards from the 90s are still supported ;)