While I agree that this might be a practical and effective step... changing my number costs me a lot of money in terms of lost revenue and expenses, I have business cards to reprint and contacts (business and personal) that I'll need to update. Considering phone companies could simply block these calls if they so desired I don't see why I, the customer, need to absorb such a large cost just to keep my life sane and, after absorbing such a cost the robo calls might just find me again.

I receive more spam calls than spam emails and, being familiar with the underlying technical details of each system, that is absolutely ridiculous. Email was built in a time of pure optimism, there is no central switching authority for emails and there is no cost to sending an email other than jiggling some electrons - telephone calls are highly metered and monitored, they generally pass through several organizations that have been endowed with a high measure of trust to police and shepard them to their final destination. There is no reason other than the monetization of the system that these spam calls are allowed to exist.

Yes, the change your number response is total BS. Not just for all of the reasons you mention which are totally valid, but for the simple fact it is just a cat&mouse game.

Phone numbers are not some cryptographically generated string that would take a while to randomly create. You can literally just start at a number and increment until you've reached them all, so that the spammer doesn't even need to know your number. Your number just got reached because it was the next one in the list.

The numbers they call are not necessarily random. I was torturing one “reduce your credit card fees” guy by giving him 3 wrong credit card numbers in a row. He got mad and started threatening me with terminating all my credit cards - which was hilarious because just the moment before he was asking their numbers. But then to substantiate the threat he disclosed what knows about me. My address, my phone, my car make… the only thing they got wrong was my name - they used my son’s name instead of mine.

And other callers called me my son’s name a couple other times. So there seems to be some database that some of them share.

Phone number often yields address, which often yields street view for the car make. Doesn’t sound like they had thaaaat much.

Well, I have 3 cars, 2 sons and 1 daughter (and me and my wife are still alive too, you know). But robocallers are stuck with the same car and the same person: 1/15 one occurrence, 0.0000013 five occurrences.

I would expect a phone company to throttle multiple failed dial attempts to nonexistent numbers. Otherwise you could DoS the system.

Shoot, in the old analog days, you could literally get the physical tumblers in the telco's switch to stick in an incomplete state and create a party line. DoS'ing the phone from too many wrong numbers is the least of the issues here.

There is definitely more to that - I'm on a pretty common 650 area code, and my spam calls have gone down from 1-2 / day a year ago to less than 1 every couple weeks.

Spammers have currently defeated SHAKEN/STIR. A signed call is more likely to be a robocall than not a robocall. This is thanks to shady phone companies that will sign calls for anyone or intentionally cater to scammers. https://transnexus.com/blog/2022/shaken-statistics-september... This is like when DKIM was first being deployed spammers adopted it first.

But once enough people lodge complaints about these calls the shady company will shape up or get their keys revoked, right?

It significantly increases their costs though. As in the parent ruling here, a shady phone vendor that doesn't take steps to prevent spammers they will no longer be able to route calls to the US.

I thought shaken/stir would help too. I receive a lot of spam calls- and now I receive backscatter calls from people who I “called” (my number is now being used as outgoing cid for robocalls- yay.)

It’s infuriating and undermines the utility of the phone system. Might as well give up and try again at this point.