Pay Pal - please prioritize a proper 2FA with an authenticator app. Any authenticator app. SMS is NOT secure for all the reasons other people have listed. The Only reason you want to use SMS is to collect phone numbers. If a proper security system was in place, no one would be giving you their phone number. Just another key piece of personal data that eventually gets leaked. Authenticators are not bullet proof themselves but are a great deal more secure than SMS. To me, it seems you are prioritizing your own needs ahead of your clients, not a good look.
Did I also mention I don't get the SMS reply from you anyways adding so much additional time and frustration. Prevents me from using your service more than what I would have.
--- end of Rant.
