Yeah, it does. It matters a hell of a lot that alcohol isn't safe, and there are a whole bunch of very well-known problems associated with using it regularly. Same for most medications. Many aren't super safe, and there is a fair bit of research and information dissemination required to make sure doctors and patients know the costs and benefits. When we fail at doing that, it causes a lot of harm to a lot of people. You should be able to make your own call, and that means knowing.
The really creepy thing about this conversation is that there is a shitload of money to be made by concealing the hazards of marijuana use, just as there is for alcohol and cigarettes.