To preface, I could count on two hands how many times I have used. I’ve always been against it’s legalization, because of the the perceived effects insinuated by your question, as well as I don’t think most people can act responsibly. With that said..
On a personal level, no, it hasn’t changed or impacted my life in any way. I haven’t noticed any additional crime, scum hanging around, etc. Although, I live in an area with fairly high crime rates and poverty, but this is mostly due to the number of prisons in my area. I live in a good neighborhood, so I am insulated, I suppose. Weed has been legal here for quite some time medicinally, and doesn’t have the same negative connotation has other places I have lived. Too be honest, I don’t think many additional people, like myself, are using due to the legal change. Instead, it just gives people a more convenient place to purchase. Everybody who wanted to use before, either got a script, or just had a dealer. I dislocated a finger and was offered a script, really not hard to receive at all.
On a non personal level, from what I hear, DUIs are up. Also, a serious issue is that owners’ of dispensaries cannot put their money in a bank, because banks are federally insured, and MJ is federally illegal. They end up leaving the money in safes in their shop, and there have been quite a few break ins. I have a banker friend who says that people frequently come in to open an account, claiming they are in the agriculture business.. he’s apparently had to go through quite a bit of training to identify ‘money laundering’.
On a positive note, a taffy is like $3 and will put you to sleep.