Don't sell the bear's hide until it is shot, that's a Dutch saying.
I think the English equivalent is: Let's not count our chickens before they hatch.
Trump is still not without a chance in this race. Yes, things look good, but so did HRC until a few weeks before the elections.
And the GOP is so woven into the US society, they last at least more than a generation to come as the counterweight for the Dems in US politics.
HRC did look like an easy victory. Only problem is, she carried a lot of political baggage, and the Republicans expertly trotted those out at just the right times to spoil her chances. Biden doesn't have that luggage. His entire political career has been pretty much without scandal. I mean, sure, there's his son Hunter's connections in the Ukraine, and the GOP eagerly trotted that out already, but that turned into a big nothingburger; the voters didn't care. I don't think we're going to see any earth-shaking October surprises where Biden is concerned. Trump, on the other hand, may be mortally wounded, and it's not even October yet, as revelation upon revelation comes out. His base may not care at all about these things, but they've gotten the average, non-cult voters' attention.
The polls are in Biden's favor. Whether they are in his favor in the right places (ie. battleground states) is still too close to call, and that's what has me distressed. I don't think we're going to see another 2016, but the current margins aren't anywhere near as wide as they should be. Biden may well win both the popular and electoral contests, but if it's not decisive enough - it would almost have to be a landslide - then Trump and his base could challenge the election and refuse to concede, basically throwing the decision to the Supreme Court, and that would likely not go well.