Just learned there is also a relatively new Linux Distribution targetting ppc/ppc64 as tier1 supported platforms (G3, G4, G5, Talos II): Adelie Linux

This one may be especially interesting as they do testing on Apple PPC hardware (though X1000 also reported working). And their packages depend on musl instead of glibc C standard library, so the packages consume less resources which should make the distro run faster on low end PPC hardware.

Have to try that out by myself!