Even if you recognized it, the number shown by Caller ID is easy for the caller to spoof -- or at least it was a few years ago (the last time I paid attention).
So asking people to take the step to confirm the call is legitimate won’t work- they can’t tell until they’ve already terminated the call. It’s useless for purpose imo.
I imagine it is doing something with STIR/SHAKEN along with how many other times similar calls have been flagged as spam calls.
I have reported at least a thousand different scam calls over the past two years and so my blocked number list is so large it freezes the phone for a minute or so while it loads. Still the scammers persist…