As for "sharing economy" & drugs and - banning them outright may not be a good idea, but it sure would be best if working for Uber came with Surgeon's General warning.

New York recently made moves to, among other things, establish a floor wage for rideshare drivers similar to how there is a minimum wage for tipped workers.

Ban things that we have good reasons to believe are harmful for people (or sign them up by default for things we believe are beneficial for them), but allow people to opt out by submitting some document that basically says "I know what I am doing is likely bad for me but I accept the risks"?

This way you both protect people from their own irrationality and maximize liberty.

The vast majority of people do not read lengthy forms; GDPR updated notification requirements to reflect that. Restricting irrational behavior to limit damage to society is not new; that’s why we regulate things like usurious payday loans.

One person being irrational is not dangerous, but many people being irrational is. The Great Depression started from the fallout of everyday people mortgaging their house and their car because the stock market was advertised as guranteed returns.