Left LI to go to college in NC and never returned for that very reason. Have friends looking to do the same now as well. To quote "it's just impossible to get ahead up here".
I love LI, and I love visiting friends and family...but I live very comfortably down here and would need to triple my salary to live on LI and maintain the same quality of life. Just your property tax payment on LI is a full mortgage payment in other parts of the country!
Same boat here. Grew up on Long Island, minutes from Fort Neverlose, went to college out of state, and did come back for a short time, but when it was time to buy a home, my wife and I moved to Dutchess County, where we could actually afford a house, a yard, and reasonable property taxes. And we are both full time professionals making decent livings - but we would have no quality of life if we had a comparable, modest home on LI - all our money would be going to housing.