The "final solution" is to get one of
these.
Folks you know get through unimpeded.
You can set it to block any specific number.
Otherwise, it will answer the call, explain politely that you do not accept anonymous calls (or calls from numbers you don't know, or what) and ask them to speak their name clearly. It then calls you and tells you the name.
You can accept or reject the call.
The delight is that you don't even know there's been a call until it's done its thing.
Oh - and it's a conventional answering machine too.