Knowing my bias, let me continue.
The question 'is it addicting' has been around for ages, of course. Just for fun, I did a StartPage search on "is marijuana addicting" and looked at a lot of results. Various topics were covered, such as what does addicting mean and is it addicting.
What I took away was that the current idea is that certainly it is psychologically addicting, which has been known. Physically addicting, mostly for long term users or those more genetically prone. Can the person stop long term and function seems to be the question. For most people, the answer seems to be Yes
Also, the physical addiction is easier to break than alcohol and drugs. (I was a medic in an Army hospital during Vietnam and I saw two guys undergo near cold turkey from alcohol. Scared the crap out of me.) A few weeks they say and most of the MJ anxiety and craving are gone. But long term users are likely to have long term psychological problems that are difficult to overcome. Maybe they would have had them or already had them, but it sounds as if researchers believe the MJ causes at least some if not most or all of it.
You mentioned "weak character" being a reason people people forego responsibilities, but some of the articles called that a result of heavy MJ psychological addiction. They used to say the "weak character" thing about drunks, too.
Long ago, I taught in an inner-city high school for five years. I saw so many stoned kids who just sat and smiled, if they managed to get to school at all. Some of them were very bright. The brightest of them pointed a gun at the driver of the car next to him just for fun. I'm sure his eyes were bloodshot and he was smiling. The driver was an off-duty cop who shot him in the head. The worry I have about legalization is that the "laid back" parents will be careless about their kids getting into their stash, or, maybe they don't even care.
Anyway, I don't want to get into a long back and forth argument on the topic. I'd be glad to hear back from you, but I won't respond. I blow too much time in online discussions.
I smoked mj for about 3 years, stopped when I was 20, and this was late 60s/early 70s when it was much weaker than it is now.
I know from research and my own experience, and seeing others over the years who smoke it regularly, that it is a character destroyer, intelligence detsroyer - make rational thinking impossible, destroys initiative and clear thinking. MJ intoxication divorces the consciousness from reality, and most people who smoke are psychologcially addicted. It has many lasting or permanent effects.
It is very destructive.