Suggesting one variable explains such differences is incredibly reductive. Plus, The US is not a single country, there is federalism and you should treat all states differently since setting up a business in NY is supposedly a lot harder than in other states.
Lower taxes is irrelevant unless all your operations are in Delaware. It's a great trick for IP holding "companies" that are just a couple lawyers in Wilmington, but otherwise you are paying taxes to whatever states you actually generate revenue in anyway.
