> I think Windows and Linux both support them.

Detached debug files has been the default (only?) option in MS's compiler since at least the 90s.

I'm not sure at what point it became hip to do that around Linux.

Since at least October 2003 on Debian:

[1] "debhelper: support for split debugging symbols"

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=215670

[2] https://salsa.debian.org/debian/debhelper/-/commit/79411de84...