If you enable advanced data protection apple cannot recover your account. You need your recovery keys or a designated recovery contact.

The apple doc implies (to me) that a SIM swap only works after you authenticate on an apple device (e.g. using your password) even without advanced data protection. I have never tested that.

You can use the long process (many days) to recover an account assuming you haven’t enabled advanced data protection. I’m okay with that as it is perfect for my grandparents (I had an older relative who got their account back through this method).

I get that you could SIM swap to recover other accounts (not Apple) if they have SMS as a recovery method. That sucks and it really sucks for people who don’t get that an email or SMS recovery can be a giant hole in security.