Biden’s up only 7 on average in the polls, not 10.
If Biden only wins nationally by 3-4 percentage points, Trump still has a good chance to be re-elected thanks to the electoral college. So really if the race tightens another 4 pp in the next few weeks before people start voting it would be tied.
Problem is that convention bounces tend to fade.
I firmly believe rats will do anything cheat they will not allow Trump back in