The public shaming and scolding for Trump support in 2016 is nothing compared to what it is now, and the blatant attempts to suppress expression by anyone but Dems on social media have been off the charts in comparison to then. Polls are even less respected, and Red voters even less likely to respond to them, than was the case in 2016. Even assuming their 'Improvements' were actually correct, there are other factors in play that didn't figure in 2016 so I wouldn't put any stock in 538 or any other poll results.
There's absolutely no enthusiasm for Biden anywhere, except possibly China. The Dems are counting on the Trump-haters and identity politics, but there are indications that Black and Latino voters aren't keen on Biden at all and a larger-than-usual percentage of both will defect to Trump. and the rest won't turn out the way they did in the past for the Dems. To the extent assumptions about those voting blocks are built into the projections, they are going to be inaccurate.
I truly hope pure negativity and hate don't carry the day, and people turn out for positive good, with the fraudsters swamped by real votes for Trump.