>Call frequency went down after cold calls could be reason for non-trivial fines. So if I am in the mood to answer, I always ask first for company ID, verify online bevore deciding which kind of fun to indulge in...

The fine is non-trivial here too (close to 300€, which is pretty much standard salary for common labour), but I haven't heard of a single case when anyone even tried to sue. Most people, I'd say 99,9%, don't even know the law exists (which is generally the case about laws nowadays).

The dismal quality of the whole business is discouraging. In these nine years since our return from the US, not one call lasted more than one minute, and our response ranged between "no, thanks" and unprintable. And they still haven't taken our number off any list, despite the 0,000% efficiency of calling it. Because there's no quality control, zero feedback, they simply don't care. Their job ends when someone responds to the call, no matter how. They don't seem to have even an optiongroup to note down the response type (I'd suggest range of "angry", "disinterested", "neutral", "curious", "gullible").