Polls are snapshot in time. All that is true. But the polling may have changed dramatically, albeit temporarily, because of the perception Trump isn't taking Covid seriously after he took the joyride while in the hospital.
2016 General Election - Clinton 43%, Trump 39% (Rasmussen Reports 10/9-10/11/16)
How do they have Biden up 12%
...and he’s clearly right because healthy people don’t die. In fact most don’t even get symptoms.