"...when you had repeatedly said that politeness had worked for you when I had repeatedly said it hadn't for me..."
I only said it once. After that, I replied to other people who attacked my statement, trying to clarify it for them. I didn't reply to you when you said for a second time that politeness hadn't worked for you. I didn't reply to that because it was not an attack on my statement. You were just saying that you've had a different experience, which I don't doubt, and which has no bearing on anything I said. I only replied to you after you appeared to be complaining specifically about my posts.

"I see no reason, however, why telling a caller their call is unwelcome, inappropriate or otherwise a nuisance shouldn't work as well as politeness."
I've suggested three possible reasons why those other methods might not work as well as politeness (and I made it clear they're all just guesses). Are you saying that you've considered all three and are sure they don't make sense, yet without saying why you think that? Or did you simply not notice them?

As to the 3 specific cases you cited:
- I've already said that I haven't found anything that stops robocalls.
- My polite method did not work on the Indian guys "from Microsoft." In that case, after several attempts at the polite method I resorted to a very impolite approach. It was very loud and filled with profanity and ethnic slurs. I'm not very proud of it, but it did work in that case. It's the only time I've done that, and I still think that the polite method should be tried first.
- As I said before, your calls for Mr Ball or Mrs Clements sound unusual to me. I've never experienced anything like that. If I did, and if polite methods didn't work, I might try lying. For example:
"Yes, this is Eloise Clements."
"Yes, this is Mrs Clements. May I have your zip code and the last four digits of your account number?"
"I'm her daughter. My mother passed away last week. We're just here to clear out her apartment. Is there anything I can help you with?"