You should enable MFA yes. But it’s definitely not reasonable to expect a forced half-assed version of MFA that keeps changing when you DON’T enable MFA. OP should have migrated the account before wiping the phone but this behavior was not caused by them.

Apparently they’re called backup codes now. I could swear they used to be called airplane codes (because they’re offline ig). It’s just some randomly generated 8-digit codes.

The most annoying part is you may get this for a previous phone even if you have registered a new phone. If you really want to avoid Google’s forced MFA the best way is to actually enable MFA and generate some airplane codes. Those can generally be used regardless of what Google asks at the time and you can store them offline or even memorize a couple. Probably not as secure but at least you won’t get locked out.

The free version of Spotify is really not worth it. Even Youtube music gives you a better experience.

Tasker. Basically an interface for writing scripts for your phone. Even if you don’t have a use case in the beginning you’ll start finding things to do with it.