As the numbers stand now, I totally agree with you. You also have this:

Trump has lost his senior advantage. And that could cost him in November.

https://www.yahoo.com/news/trumps-lost-senior-advantage-could-104438826.html

The problem with thinking the election is in the bag at this early point in time is the official campaign season doesn't begin until 1 Sep. End of June Polls are interesting.

2020 Biden up by 9, results unknown
2016 Hillary up by 5, lost although she won the popular vote by 2 points.
2012 Obama up by 5, won by four
2008 Obama up by 7, won by eight
2004 Bush up by 1, won by three
2000 Bush up by 5, won although he lost the popular vote by 0.5 of a single point.
1996 Bill Clinton up by 16, won by 9
1992 Bush up by 6 over Bill Clinton, up by 1 over Perot, lost by 6
1988 Dukakis up by 5, lost by 8
1984 Reagan up by 8, won by 18
1980 Carter up by 3, lost by 10

Kind of a mixed bag there. Carter, Dukakis, G.H.W. Bush and Hillary who led at the end of June all lost. But Hillary is the only one to lose since 1992 and she won the popular vote. So perhaps having an early lead at the end of June is more important than it was in the past. Time will tell.
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It's high past time that we start electing Americans to congress and the presidency who put America first instead of their political party. For way too long we have been electing Republicans and Democrats who happen to be Americans instead of Americans who happen to be Republicans and Democrats.