To be fair, the summer Covid spike was likely an unusually bad period for Trump and the Republicans in Florida. It was never +13 though.
If Wisconsin results tell us anything, I'm not sure if COVID spikes actually helped Biden. He was improving in the polls, but that might have meant that Democrats were more willing to stay inside and respond to pollsters.
I posted a thread about this recently, the polls did have a late shift to Biden in Wisconsin which was unusual. So maybe the Covid spike cost Trump Wisconsin.
Marquette did not
Marquette was steady the entire time, so were Trafalgar and the other "right-leaning" polls. It was only the media polls that had these weird inconsistent shifts from week to week, which tells you not that it was a "snapshot in time" (it's supposed to be, but that doesn't explain it) but rather response bias, herding, and narrative promoting.
