yea while the actual quantity seized is impressive, there are probably super labs deep in the jungles of mexico where they can yield hundreds of pounds a week. Thats why you see so many indians living in mexico, they import a bunch of the precursor chems. that huge cash bust was at the house of an indian pharma ceo who just happened to supply the cartel with raw ephedrine.
when you dont need any natural material like you do with cocaine or heroin, so the limit is only based on the amount of chemicals and space to synth it.