NYS has been going downhill ever since Nelson Rockefeller in the 60's and early 70's...yeah, I'm that old. After him, the state swung Democrat although not many noticed the change because Rocky was really a Democrat in spirit. After their fling with the Democrats, the state turned to Pataki, a Republican. I don't recall much of him, he was that influential. Then they swerved Democrat again.
NYS got screwed because Rocky taught the legislature how to really shake down the companies and the people. The labor unions were right behind those policies and helped drive business out of NYS, though Rocky got the ball rolling. This happened while the older rust belt industries were being decimated by the Japanese. The later free trade agreements only accelerated the decline.
NYS never gets out from behind the 8-ball. It is a shame really since they have decent colleges and universities. Somehow, they always manage to fail to capitalize on those. The taxes are enough to prevent many new companies from getting started in the state. And even if they did have tax incentives for companies, they'd have trouble hiring because NYS believes in taxing the pop. out the whazoo.
The local governments also got into the taxing and bureaucratic treadmill. Erie County, where Buffalo sits, should whack about half of their county politicians and the City of Buffalo doubly so. The decrease in pop. was large yet they are carrying on like their pop. was 3 times what it is currently.