Telco companies allow people to set up numbers which cost money to send an SMS to.
Then those people set up bot farms to register for Twitter repeatedly, triggering a verification text, which Twitter then has to pay.
The telcos aren't committing the fraud directly, but they are profiting from it.
That's cleary being an accomplice.
That's like a business that sells a service of smashing windows of any car that drives by your home.
My private number can't send texts to premium numbers, that an automated 2FA system could is so ridiculous I would never even try it. I guess that's why they're better fraudsters than I can ever be, they expect this level of stupidity while I'm surprised.
Twilio (the main SaaS company that does this) doesn't have a good solution here
https://www.twilio.com/blog/2015/08/introducing-max-price.ht...