Marijuana is absolutely a drug with downsides. There are also upsides - for example I enjoy my life more. I also enjoy alcohol, sometimes to excess. I acknowledge I have taken likely years of my life away through my actions. I have also dabbled in cocaine and ecstasy. I don’t think those drugs should be totally illegal either.
My point is we all make our own decisions and are forced to accept risk. Sometimes you just have to live. Otherwise why bother living?