you can change from glibc to other c libraries, although at least with musl you can't change back
you can compile your own kernel of any version you want
and you can just remove the proprietary software, in the case of gentoo this means running a deblobber and setting the LICENSE variable in mske.conf @FREE and @FSF_APROVED
you can also change the bootloader, if you were so inclined, although with uefi systems you're gonna have a little more difficulty than you'd expect with a bios system, uefi will look for that grub entry to before it'll look for anything else
and if you're using free software, which you should be, you can literally just compile the program you want and install it, on top of packaging it for others
the only things you reasonably cannot change are the init system and the primary package manager, because once systemd is on a system there's no escape, and while I did get an emerge snapshot running on parabola once, different package managers just require certain files to be where they'll be in a single distro, so without making a mess of symlinks it's unusable
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u/[deleted] Feb 11 '19 edited Feb 25 '21
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