[viraptor]

This is not workable for an average person though. Also people just don't get how telephony works today. Here's an example: which of these is a call from out of US:

- call from a person in Canada, legally using a valid US caller id

- call from a US mobile roaming in Canada

- call originating in the US, routed via Canadian telco back to the US

- call from a US mobile in the US, using a VoIP service in Canada, legally using the same mobile's US caller id

(None of these are doing anything illegal, and are valid scenarios)

[MiddleEndian]

Yeah perhaps I don't need to block absolutely anything outside the US (and Canada), but clearly at some point there's an initial caller. If at any point I hit a hop that's not trustworthy, I don't want the call. If you can't reach me without resembling a telemarketer, I probably don't need the call. If legal but irritating companies find themselves unable to serve calls, I consider this to be a positive. If the phone system collapses, I consider that the be an improvement over having to sometimes be reachable over the current phone system.

[boring_twenties]

Blocking all of those would be vastly preferable to what we have now. I get about 5 spam calls a day, so the only thing I can do is disable all incoming calls altogether. Blocking all of the things in your list, while hamfisted and far from ideal, is better than that.