The issue with many of those distros is that it usually means that you have to install everything from 0.
Arch is good at this because the archinstall script speeds it up and you don't have to choose a DE. But with other distros that use a graphical installer, you are forced to use whatever they ship as the default desktop environment.
edit: And holy shit properly configuring Btrfs subvolumes from 0 is something that I tried with voidlinux and I ended up breaking the entire install.
Doesn't timeshift work? If you installed fedora with Btrfs which is the default it should work unless the default subvolumes used by fedora are not compatible with what timeshift expects.
Sorry if you meant to say that they should have it by default and you are already using timeshift.