> that's what the DEA shut down by tightly controlling pseudoephedrine, where before meth using meth makers were making meth and distributing it.

Phosphorus-ephedrine meth, aka shake-and-bake.

> It certainly seems like prohibition is just making things worse and making it more lucrative for the least ethical of black market producers.

I don't think P2P meth is any worse than what came before it. Prohibition is making things somewhat worse here for legal access to pseudoephedrine, though.