I think it's OK say that Marijuana should be legal but acknowledge that the concrete proven medical benefits attributed to it are pretty marginal.
Even more: there's basically zero medical benefit to tobacco, and if there are 1 or 2 areas where it's slightly beneficial, there are a thousand where it's vastly worse. If tobacco isn't a schedule 1 drug, there's no way in hell marijuana should be.
I don't use marijuana and have no personal stake in this. If it were federally legalized today, my own personal life wouldn't change a bit. I just think it's ridiculous that we're clutching pearls about whether marijuana is good for you when other things that are objectively much worse for you are perfectly legal.