[Senji]

You should be able to forbid incoming calls from certain countries on your line. Or international calls at all.

This would be very useful for grandparents. Why isn't this a thing yet?

[dangerboysteve]

because VOIP will get around that.

[Clubber]

Yes, but it will increase the cost to the scammers and filter out the ones that can't figure it out.

Possibly have a reroute rather than a block so it's harder to detect. Reroute the calls to a voice mailbox that essentially saves to /dev/null.

[Senji]

Can you reroute to a pay service? So every time they call you they get dinged?