I shall say it again, the legislators are barking up the wrong tree. The telcos need to enforce caller ID and anonymous call blocking properly, not the half-arsed 10 specific numbers and maybe block anonymous calls if they're in the UK, or maybe not, depending on wind direction and the position of Mars. Caller ID spoofing should be an offence too. If the caller is in darkest Mumbai, the caller ID should damned well say so. Translating the different caller ID schemas is not rocket science for an industry that can now cram video on demand down a flaky fifty year old pair of copper wires.
The problem remains that cold calling, scams and fake tech support calls are lucrative for the telcos. Until that is addressed, this will continue. Giving the subscriber a little control over who they allow to make their 'phone ring would be a good start, too. Yeah, yeah, TruCall. It's not enough to expect granny to pay for a box to stop her getting scammed and mithered every five seconds because some telco wants the termination charges.