PenguinPPC will NEVER DIE
Here are a few non-stale links that work as of August, 2022
Bootloaders for Old World Power Macintosh computers (beige G3 and earlier)
Debian PowerPC network installation ISOs
https://cdimage.debian.org/cdimage/ports/snapshots/2022-12-09/debian-11.0.0-powerpc-NETINST-1.iso size - 356MB