Maybe not directly, but that's the cause. Most people want to live somewhere clean, with low crime, good infrastructure, and jobs. Most cities have tax-funded programs for all of those things. If they aren't on par, then there's two culprits: a) not enough tax dollars, b) taxes aren't being used effectively. Personally, I think it's almost always the latter. You can look at the historical effectiveness of most programs, and coincidentally, they seem to get less effective as more money becomes available.

There are other things that governments do besides tax and spend. Things like individual and civil rights and freedoms, etc.

The United States doesn't have a monopoly on liberty and civil rights. 45% of all countries are "free" using The United State's own definition of the term [0].

[0] https://en.wikipedia.org/wiki/Freedom_House

Indeed, seeking particular rights and freedoms might be a reason to live outside the United States.

It's not clear where the emphasis on taxation is coming from. It's not in the underlying article and the polling shows only two wealth categories.

Based on the data it's age that determines whether or not to leave the US, which makes sense since there'd be shallower roots to leave behind.