Backups are only good if you 1) do them and 2) test them (eg, try to restore what you backed up).
Note also that backing up to a drive in your house protects you against some but not all failure modes (ie, not against a physical disaster -- fire/flood/storm, and possibly not against a ransomware disaster (if you leave it plugged in)). Base your backup strategy on what you're trying to prevent.
Re google music, there's no way that isn't heading for the google graveyard. I wouldn't get attached to it. Not to mention it kinda, well, sucks. Its from The Search Company. Guess what you can't do on it? That's right, search on decade or even exact year. It heavily pushes you to their streaming in which case you get ads unless you are subscribed (?).