Really? News to me. You live here? (Not asking sarcastically.)
I've lived here 27 years, I've found in general everyone's too busy and goal-driven to get heavily messed up with drugs. That could be a function of the crowd I hang out with / my profession.
If you have first hand knowledge otherwise, I'd love to hear it.
The HBO comedy series Silicon Valley does give that impression. Yes it’s a satirical comedy but good satire has to have an element of truth in it to be good!