That study is flawed in so many ways it is laughable the business journal picked it up. There are far too many variables that are loosely related that were added together (similar to a multicollinearity problem.) Another major flaw of the study is that, based on their criteria, a city that did not suffer from the recession at all would appear to have also not recovered.
From what I've seen from wallethub, it's about like JD Power awards for cars. Great to throw on your marketing material if you win, but certainly not something to take seriously or worry about if you don't.