Businesses don't set up shop in NJ because it's cheap; that's laughable at best John, they set up shop in NJ because they can make a better profit here than any other suffering state.
Detroit took a nose dive when they lost their comparative advantages in the auto and real estate markets. None of that had to do with taxing the rich, medium classes, or even cutting off services for the poor.
Until NJ loses is comparative advantages, will it suffer the severity of what now is Detroit. Everything is a balancing act, and just because Detroit is pinned to the ground right now on the proverbial see-saw does not mean they can't come back by regaining another advantage like finance, information systems, and so fourth.
Like a business, NJ has to find a way to cut costs and cut out the excess. A avg 2 bed room house in NJ costs over 300k dollars. The cost of living in NJ, NYC, and parts of PA is a larger issue inpart caused by many smaller issues.
Businesses don't want to pay average skill laborers enough so they can afford their 300 thousand dollar town homes (and 300 thousand is actually being modest. New construction housing goes for more like 400 and up) so they either stop hiring or lay off. So tax or no taxes, people are still going to leave.
I would continue my theory but my eyes are shutting and I will have to return later...