I think what I would is a level playing field. If I get a call like that I cannot trace, I would expect that I should be able to do the same. If I am held to a standard that is not conducive to privacy, so should the person on the other side of that call.

But.. there is money on the line. Clearly, money from telemarketers/scammers/whoever is using this tech is enough to make telecoms hesitate from actually doing something about it.