I'm not certain, but I think on my phone incoming calls that fail SHAKEN/STIR show the caller id in red rather than black text. I'm on T-Mobile. It also shows "Number Verified" or something like that.
Now that you mention it, I believe I have seen a couple of red flagged calls, but I still get ~3 calls a day from a very aggressive business loan spammer, it's always a new number and never flagged.
Now that you mention it, I believe I have seen a couple of red flagged calls, but I still get ~3 calls a day from a very aggressive business loan spammer, it's always a new number and never flagged.