Yes, the average person living in Connecticut or Massachusetts remains better off across many metrics (health and education among them) than the average person in Texas or Oklahoma. There are many differences between the New England and Mid-Atlantic states and the deep South and Southwest, and the presence of state income taxes is not the most significant of them. People living on the Upper East Side of Manhattan have above-average incomes and education levels, too, and the city’s income tax has no more to do with that than does the fact that they pay very high rents, drink a great deal of coffee, and read Monocle.
Population matters. Texas, for example, has better standardized test scores for black, Hispanic, and white students than does Wisconsin, but it has lower average test scores across the population as a result of its different demographic characteristics. Likewise, residents of north Philadelphia pay the same wage tax as residents of Rittenhouse Square, but their health and education lags as far behind that of Philadelphia’s better-off residents as the living standards of people living in the South Bronx do those of the denizens of Fifth Avenue. Suburban New Jersey and urban New Jersey hardly feel like the same country, let alone the same state; the same goes for suburban and urban Maryland, Cleveland and its suburbs, interior and coastal California, etc. “Strong and active government” often is part of the problem.