There are hundreds, you'd have to play whack-a-mole with myriad VoIP and second- and third-tier wireline providers to get them all. And that presupposes that t

There are hundreds, you'd have to play whack-a-mole with myriad VoIP and second- and third-tier wireline providers to get them all. And that presupposes that the accounts are even legitimate. A lot of robocalls are delivered through hacked SIP credentials. I know people like to pick on them because they do seem to turn a blind eye to all but the most egregious spammers, but Twilio is only the source of a lot of spam calls because they are a large carrier in their own right. It's like all of the people moaning about Californians being the most common place of origin for people moving to their area; that's true, because California has the most number of people.