You're correct, but back in the day, all nodes were trusted nodes, so would have been a lot of overhead to authenticate all this stuff. Hasty regulatory oversig

You're correct, but back in the day, all nodes were trusted nodes, so would have been a lot of overhead to authenticate all this stuff. Hasty regulatory oversight in a fledgling industry led to the current situation. STIR/SHAKEN actually has the potential to do things correctly, as a call Digital Attestation Certificate has to be supplied... but telcos make quite a bit of money off of scam callers so don't expect them to move quickly, and I'd expect them to implement it in the absolutely poorest way possible.