Using 538's urbanization index from the linked article - which appears to have been calculated in 2019, as well as the preliminary results at time of writing according to Dave Leip's Election Atlas, we can investigate this.
As in 2016, we find a fairly strong positive correlation between FiveThirtyEight's urbanization index and the two-party vote share in the state. The correlation coefficient between the two variables is ~0.66, and the approximate linear trend-line plotted in blue on the graph below has a gradient of ~13.2. This compares to the correlation coefficient reported by FiveThirtyEight of 0.69 in 2016; while the coefficient has reduced in magnitude, it is such a small change that I'm unsure we can draw many conclusions from this.
Vermont is once again the only outlier, with a studentized residual of 3.87; the state voted overwhelmingly for Joe Biden, with a two-party advantage of D+36.6, despite having a low urbanization index of 8.84. Florida was, again, the most urbanized state to vote for Donald Trump.
Running the numbers on the 2016 presidential vote margins myself, rather than relying on the article, I get a correlation coefficient of 0.68, so pretty much the same as the article's calculation. The gradient of the trend line is slightly steeper than in 2020, at ~13.9.
The code used in this answer can be found on GitHub.