It is indeed disappointing why it has come to this... even though I listed my name in the Do Not Call Registry list... such a useless list, however.
What I do I save the number (of all my unwanted calls) and name them DO NOT ANSWER.
The negative aspect of this is that they (the unwanted callers) use my phone minutes.
Only if you answer. If someone leaves a msg and I want to talk to them -- OK. If I do not recognize the caller, I don't answer the call. No minutes lost. The ones that tick me off are the ones who text me. I pay for that whether I want to or not.