It's interesting that you assume it's a myth. I can personally attest to answering spam calls, politely asking to be added to the do not call list, and still receiving calls from the same spammers over a period of months. Eventually I just downloaded a call blacklist app.

This depends on the caller.

A lot of the calls I used to get were the ones where they spoof a phone number that has the same first few digits as yours to make it seem like a local number and then the caller is a scammer “You owe money to the IRS”, “Your computer has a virus and you have to pay to fix it”.

Engaging these callers is probably not useful.

Which makes them easy to spot if you get a number from a far away area. The only calls I get from my phone's area code are misdials or spam, but my doctor's office stands out without a whitelist.

No, it is useful, they still don't want to waste time calling people that aren't going to take part in the scam.

Man i should get you to talk to my spam with that magic +5 robot charisma.

Unfortunately, it still won’t prevent my number from being spammed. There is no human to talk to. Any indication you are alive is a confirmation your phone number is worth calling. The only thing you can do to convince them is not answer or somehow communicate a likely disconnection from a human.

So have you tried the approach I am advocating for a meaningful amount of time, say a week or two, or are you just sure that it won't work and thus avoid it because you are worried that you will do things like confirm you are worth calling?

Honestly I haven’t collected enough sample attempts to be sure. However, not answering unknown phone numbers seems to have worked very well.

A lot of the spam calls I get are just recordings or they just hang up once I pick up. Hard to imagine it would help to just say "please add me to your do not call list" into the void...

I also receive a lot of those (around ~5 a day, for more than 5 months already). It is really annoying and makes me wish I could just block numbers on my phone.

Try listening to the end, there is often a number to press to have them stop calling.

The internet myth is that this marks you as someone to keep calling (because you listened), but really they will stop.

That you had some luck being removed from some legitimate call lists does not mean that you can dismiss these extremely common tactics as "Internet myths." There's a whole spectrum of spam callers that ranges from respectable businesses all the way to outright scammers. Some use illegal tactics like the ones you're trying to say are a myth and literally everyone I've ever talked to in person about the issue has had a similar experience.

The illegal tactics aren't what I am calling a myth. It's the idea that asking illegal callers to stop doesn't work that I am calling a myth. Even scammers are concerned with efficiency.

I mean, I get ~1 unwanted call a week across a couple of phone numbers (that I answer and ask to stop). Other people are saying that they get a dozen a day and giving up on their phones. My anecdotes work for me.

You probably have to stay on the phone while they do it though.