I doubt if any of the well known drug companies would want the liability or the reputation.
Besides, Amsterdam tried to relax their drug laws and now they realize their mistake. If it weren't for the behavior of meth addicts and potheads, their drugs of choice would be legal.
Amsterdam is half Muslim. The Amsterdam elementary school kids are 80% Muslim. Amsterdam has a Jewish liberal apologist for the Muslims as Mayor.
So, the reason pot, red lights and the famous Dutch tolerance is receding is not why you think. It is the population that is changing.
If you go, and I suggest you do, because in fifteen years it won’t be safe, do not walk( yes they are that close ) far outside the usually Amsterdam tourist center. You will be in Islam land.