I am making some general comments here and I am also not speaking about the ease some people who have chronic ailments get from smoking marijuana.

What you have listed as "BENEFITS" from smoking marijuana are only forms of temporary relief and not solutions to any of the mental conditions that are at the root of the problems.

It would be a rare instance of necessary short-term ease that I might consider smoking to be of limited benefit. However, if a person has the means (access to information and other resources) to develop, then settling for smoking marijuana could be considered an abuse.

Even if you use the plant and get a reprieve from stress, you still have to address the underlying cause of the stress. If you use the plant and get some insights, you still have to develop to be insightful all the time without it.

If you smoke to calm down, here are a couple points I can make about that: first, you wanted to calm down, and second, you still need to develop to be able to calm down on your own.

If someone who smokes is in the habit of abusing their partner, then smoking could be the catalyst that is removing inhibitions that could have otherwise allowed for more consideration of actions. One could also lose inhibitions and become more courageous to do positive things. The point I am making is losing inhibitions can be both good and bad depending on the motivation and mindset of the person involved. Not being able to carefully evaluate at every turn without smoking is a shortcoming.

Not addressing shortcomings like, weakness of character, short-temperedness, lack of confidence, inability to access and feel connected to different states, being incapable of experiencing things like food and music on deeper levels but still continuing to use drugs or alcohol is self abuse. Panaceas, such as smoking marijuana, are only temporary escapes from dealing with core mental issues.

All that you have listed so far are issues people should be working on to overcome (develop) but, for the most part, people stay at the stage of using the short-term relief as if it is a cure. Smoking can be considered a comforter, like ‘religion’, that many of its users are enslaved to by the false sense of comfort they get from it.

While I do agree that marijuana, like alcohol and other drugs, could be useful in some limited scope, I think people should be developing to improve themselves for the long term and anything that impedes that is not a benefit. Proper mental development is paramount to the development of the African community. What you have listed as "COST" is way more common among the smokers I know than a real conscious effort to develop beneficial abilities.