The vast majority of scam calls are using forged callerID that tests as a non-connected number. Why aren't these being filtered automatically?
The vast majority are also injected into the global phone system using forged routing origin data (What used to be known as SS7 ANI data) - and as such TalkTalk is being scammed too, because it gets no termination revenue from the calls.
It's in your financial interest to test for and block these, so why isn't this happening? And once scam patterns are noticed coming from specfic interconnects why aren't they being stomped on?
What about the often-mooted idea of having a way of endusers being able to report that the last call was a scam by dialling 1571 and a code after the call, (or 7725) etc, then using automated statistical collection to more easily identify and block scammers?
The vast majority of people don't report scam/nuisance calls because they don't have time to do so - making reporting easier would go a long way to solving the issue - and if you're using aggregate statistical data (eg, must be reported as spam by 10 different customers) it avoids malicious attempts to tag individuals whilst still catching SIMs or landline being used for illicit marketing campaigns.
We have vast levels of data gathering and communications tools at our fingertips which can be used for constructive purposes - yet telcos are notoriously hard to deal with and collating reporting data to thwart criminals is extremely difficult.
This brings up the question of why there are extra charges for facilities to refuse calls (anonymous or specific numbers or on a spam blacklist) when these features are built into the telephone exchange and cost nothing to actually provide other than the cost of someone enabling it (if enabled by default, the cost is essentially zero)
As a former telephone exchange network engineer (the real kind, with university qualifications) I'll point out that the only reason we didn't offer the advanced features built into digital telephony switches as standard items when they first started becoming available was because someone decided that we should charge extra for them, not for any valid technical reason.