I'm very interested in knowing the actual current state of affairs WRT spoofing and a lot of people make claims without evidence which makes it hard to find out. I thank you for providing your evidence here because it does sound like some carriers are still not enforcing. Which is obviously a problem.
Mine literally come from the verified coinbase phone number and say coinbase and everything. If I didn't know for sure they are not calling me I'd think it was real 100%.