I imagine that the $2k price point is not entirely arbitrary - people seem to be going for that price point. I know I certainly would, and the only reason why I am not paying the scammer directly is because I doubt they would keep their word.
With current infrastructure, a caller can say they are any number they want because the network trusts clients to report themselves accurately.
It's an interesting DDoS, if an attacker sends a lot of requests to a website, there are solutions against it, but what about a lot of calls to a number?