Now, it does become a bigger problem if the current spammers publish their source code and more join in.
There’s absolutely no effective controls to stop it - here is the Wild West still - so the elephant is the room is anybody can flip the table at present.
The good news is much of the anti spam and anti phish technologies over the years (Real time Block Lists etc) can be reworked for here. The bad news is that’s a long way off realistically.