Discord does provide a .deb, but I’ve never found a repo that carries updated versions. I’ve found plenty of hacks that download the latest one and install it every night, but for whatever reason, it’s not kept in the various Debian repos out there.
The kids mostly use Mint with one Ubuntu machine (driver issues that worked on Ubuntu, but not Mint).
I’ve only barely used steam myself (no time for games: see having many kids), but I know the kids often do have to do various tweaks for games at times. I let them have full sudo on their own machines with a scorched earth policy if something goes wrong. Mostly, it seems to work and they don’t bug me much.