Has the traffic death toll in Colorado changed since legalization?
Are potheads in CO sitting at stop signs waiting for them to turn green?
Or do those who smoked pot for thirty years still claim to not be addicted?
No, it has not.
Neither has the crime rate changed significantly, in spite of the appalling stories that get selection for publication.
One thing that has changed is that you cannot find large warehouse buildings anywhere in south Denver right now. And industrial electricians are doing a very profitable business wiring up grow lights and security systems. But the smart ones get cash up front. Growers have a very bad reputation for slow and non-payments.
There are a ridiculous number of pot shops in every small town. I expect the market is becoming saturated and many of those places will be gone in a couple of years. The easy money has already been taken.
Tax revenues to the State Government have been somewhat disappointing too. There has been a lot of money available, but every organization in the State has lined up to take a piece and the demand exceeds the supply.
As for the customers, they are draining off their brain cells with the incredibly potent cannabis products available and no doubt will show long-term deterioration analogous to that of alcoholics. That problem is self-limiting. "Think of it as evolution in action".