I smoked pot / ate hash oil (not legally, for the most part, although in some countries it was fine) the first time my PTSD got bad.
It helped about as much as any other drug I used. Ecstasy, MDMA/MDA (not for therapy purposes, just recreationally), LSD, Psilocybin, Mescaline, Peyote, Opiates of many colours, Cocaine, Alcohol, Benzos, etc. Chemical Distance? // Better living through chemistry? Is just fawking useful, sometimes. Also, they have some well known downsides. Being able to choose my mood helped my PTSD absolutely not one iota... but they all helped me remain highly functional in my life. This time around? I decided to f*ck up my life in brand new ways, since I’d already done the other. The end result was that I DID avoid the inherent problems in habitual drug/alcohol use/abuse, but my life also took a rather steep nosedive. Comparatively.
So for me? It’s very much 6 of 1, Half a dozen of another. Pick which problems you want.