I feel like a time delay would help with this too. If it takes an extra 24 hours and you get notifications by SMS and email during that period with the chance to call "fraud" it stops most of these attacks which take control of e-mail and phone simultaneously.
I get that makes life much more difficult when you are travelling and have your phone (and therefore SIM) stolen, but given the severity of the current issues it seems minimal disruption. You get a burner phone for 24 hours?
You get a new SIM instantly, but it has a temporary number. Then you get notifications via SMS on your old SIM, you usually get a call from your old carrier trying to get you to stay, offering discounts and shit. Then after 7-14 days the new SIM gets the old number and the old SIM stops working.
The U.S. system sounds horrifically irresponsible.
// Replacement with the same carrier is quick, but requires physical presence with government ID (passport)
Same in Turkey (takes 2-6 days), but you get your replacement SIM after the transfer is cleared, you still use your old carrier and SIM during porting porting. Old one simply gets inoperable by a remote command.
I get that makes life much more difficult when you are travelling and have your phone (and therefore SIM) stolen, but given the severity of the current issues it seems minimal disruption. You get a burner phone for 24 hours?