My phone has a call-blocking feature, and I even use a service that routes private callers through an 800-number to get their unspoofed ANI. Yet one debt collector calls me from 200 different numbers. They change the number every 2-3 days. (it's for a debt I consider invalid, and beyond the 10 year statute of limitations anyway, so I won't ever pay it.)

I think what we need is an Adblock for phone numbers that categorizes all spammers, debt collectors, etc and blocks them instantly on everyone's phones.