Hi MisterM, I have moved multiple times for work purposes starting age 17 and more recently in my 40's. I have never regretted it and don't really see it as a huge deal, but it may be for some so it all depends on the person. Everyone if different.
One point though, you can leave NYC behind but you can't leave the addiction behind. That will travel with you wherever you go. You will need to beat that wherever you are and it doesn't get any easier. It sounds like you have a good program waiting in LA so good luck whichever way you go.