Yeah, a fail2ban would be great. Bell labs ushered in a lot of our infrastructure, it isn't like baby bells haven't been involved in the ecosystem that creates these tools, it looks like they aren't willing to lose any traffic.
Yeah, let's throw out the entire idea, because it is not perfect. Spoofing is the main problem here. If that was blocked the $20 disposable phone would be much harder and more expensive to exploit (his many disposable phones they would have to use to perform a single successful campaign?
Things don't happen in a vacuum, don't be so dismissive. There would probably have been put something in place to stop a $20 sim from doing these things in the first place.
You could, but you also need to take into account the number travels with the SIM, not the handset.
The SIM is you. People already buy burner SIM's, and many countries have started to implement tighter controls on SIM purchasing in order to aid law enforcement's ability to track down telephony enabled crime.