[mhzsh]

Then phone spam would be replaced by fraud, similar to what already happens with premium number fraud: https://www.twilio.com/learn/voice-and-video/toll-fraud

A bot tricks a voice service to call them, then rakes in fees.

[radford-neal]

To be vulnerable to the 25 cent charge, you have to make a phone call. Why is anyone setting up a bot to make huge number of phone calls? The phone system is meant for people to make phone calls to other people.

[mhzsh]

For types of 2FA, sadly. AWS also does it to verify your phone number when you create an account.

[radford-neal]

So the worry is that some fraudster would set up numerous AWS accounts with a number for 2FA which AWS would call, and then they'd ding them for the 25 cent charge?

If actually a problem, having the charge go to charity rather than the recipient would eliminate any monetary incentive. I suppose one is left with someone who has a grudge against AWS trying to bankrupt them 25 cents at a time...