It goes without saying that being high on anything while driving is dangerous to others. Although, in my experience, people high on cannabis just drive dangerously slow.
This differs from drugs like alcohol, which inherently increase people’s propensity to be a danger to others.
I guess we have had different experiences with the smell of cannabis, but back from when I worked in a hotel, the protocol for when a person smoked cannabis in a room was to just leave the window and door open for 15 minutes, and no one would be the wiser after that.
Whereas, if someone smoked cigarettes in the room, the cleaning process was far more costly.