Netflix definitely has trouble with this because they too lack the whole "delete all sessions" capability, so it's next to impossible to recover an account that has been compromised. My partner went through this, and Netflix support told her to delete the account and make a new one (losing all our recommendations in the process). Why they can't be bothered to add a "log out all users" feature the way something like Github or even Plex offers is beyond me.

Netflix does have that feature:

https://www.netflix.com/ManageDevices

Confirmed. I've used it

You can log out of all accounts via the Netflix website. It does take up to 8 hours last time I used it.

For posterity, I'd recommend using a passphrase if you're sharing with family. If you're using the diceware method, you get 12.9~ bits of entropy per word.

So a three or four word passphrase should be sufficient, and is much easier to memorize + tell to someone.

It especially helps with the dreaded "what's the wifi password?"

It’s easy enough to add a separate user as a “child” where you have to approve any purchases to keep them from charging anything.