As more and more states decriminalize and legalize marijuana, there will be less of that practice. Of course the Federal government could solve that one all at once. There will be less agreement on decriminalizing other drugs.
I don’t see how legal pot has that much effect on these seizures, Drugs are the excuse now but even if all drugs were legal, they’d find another, human trafficking, gun running, or gasp “untaxed loosies.