I read a study here in Australia a little while ago that showed that removal of easily accessible pseudoephedrine had done nothing to either stop the proliferation of clandestine labs, nor curtail the availability of crystal meth. They just switched to different syntheses, and there are still large-scale imports that sometimes get caught, sometimes don't.
People were still trying to claim the program was a success because they had stopped gangs getting pseudo as a precursor.
But so what? it's done literally nothing to stop criminals profiting, nor to stop people getting addicted to meth, with all the associated public health and petty-criminal consequences of that. And now it's harder for ordinary people to get effective decongestant.
It just seems that nobody is willing to admit the whole thing was pointless.
Same in New Zealand, we removed pseudoephedrine as an option unless you had a special dispensation from the Ministry of Health - mainly due to pharmacies being ram-raided for the pseudo.
The end result? The gangs just started importing pseudo, before later just switching to importing methamphetamine directly (something that Australia's deportation policies really helped with as the "501s" as we call them that were deported back to NZ often had existing connections that could facilitate the direct importation of meth).
It's a really interesting supply chain that involves organised crime groups in multiple countries, often starts in India for the precursors, then clandestine labs in Laos/Vietnam/Thailand overseen by Chinese groups in conjunction with local groups, then smuggled via the Pacific Islands, notably Fiji and Samoa where the Chinese groups have established transshipment facilities, before being smuggled into Australia and NZ by local groups who then distribute and supply it.
A new development has been the Central American cartels branching out from cocaine to meth so there's been a bunch of meth coming directly from the Americas.