LSD and Unix were both created at Berkeley. It can't be a coincidence.

In large doses over extended periods of time, they do change how someone thinks and perceives the world, perhaps for the worse. See stories of amphetamine psychosis. Those somewhat mirror a type of extended bad experience after using psychedelics, often called dark nights.

It just shows you can be an avid drug user and still make enormous contributions to STEM. It only takes n=1 to provide a counterexample to an absolute like "drugs never produce anything substantial."