Urgent to block NO CALLER ID calls

What I am specifically after is a setting on the iphone that will disable calls with call ID deliberately blocked that come is as NO CALLER ID to be routed directly to voicemail without ringing. In my case these NO CALLER ID calls placed to my phone, and that ring through to my phone, have the number deliberately withheld enabling the caller to be harrassing without consequences.

I have installed the TRAP CALL app but I wonder if this will be sufficient to protect me from the invasion of NO CALLER ID calls ringing through to the phone.

The "silence unknown callers" feature is much too gerneral and not quite the right fit to combat this problem. I often need the calls that come through from unknown numbers.

Apple engineers need to incorporate a feature in the next system software that will route NO CALLER ID calls immediately to voicemail without ringing at all.

What are other iphone users' experiences with avoiding the invasiveness of NO CALLER ID?