If your package manager is apt, you can get a list of all the packages you have installed with
apt list --installed
There’s also a command to automatically reinstall all your apps from the list, I don’t remember offhand, but I usually just do them manually from Synaptic.
As other commenters have said, some people keep their /home on a different partition so you can reinstall or install a different distro without losing all your configurations (always back it up first anyway of course). But another thing I’ve done a lot is just have a different disk or partition with all my data files on it (called ‘data’ of course :p ), and I put a link to it in my home directory. So when I reinstall the OS I do have to backup my home dir and then copy it over to the new install home dir, but it’s small and just has my dotfiles and things.
Also on the data partition I have a backup subfolder where I keep a copy of any system config files that I’ve edited (usually found in /etc/), such as my pulseaudio config, so I can restore those.
And you can always try out different distros in a virtual machine or with a live USB before making the commitment of installing one on your hardware.
FreeTube is great! I’ll wait for the normal release which is soon enough for me–when these things happen I just check it every so often, knowing they’ll figure out how to fix it like they always do.