Good luck with that. These counties have been a known standard indicator for quite a while. Saying that they are wrong and so what is just admitting that there are anomalous results there.
Sigh! Why don't you understand anything?
There's nothing "magic" about bellwether counties. Historically they have gone with the President, that doesn't mean failure to do so is an indication of anything.
As you have admitted, Biden's support was concentrated in a relatively low number of counties but as you are repeatedly failing to understand - or pretending not to - not every county is created equal. Some have significantly higher populations than others. The number of counties won isn't an indication of anything.
Trump is the first incumbent president in 132 years, since Grover Cleveland’s failed bid for re-election in 1888, to have increased his vote from his first election and not win. Trump collected more votes than any previous incumbent seeking reelection, receiving 11 million more votes than in 2016.
Biden won more votes nationally than any presidential candidate in history, but he won a record low 17% of counties — yet Biden somehow outdid Obama in total votes? If this doesn't at least make you curious about the voting anomalies, you're simply not being honest.
Voter turnout was significantly higher in this election than it was in any recent one - Trump evokes strong feelings both positive and negative. So yeah, Trump got more votes because more people voted. And remember that Trump didn't even win the popular vote last time out, I don't remember you expressing incredulity about how Trump could possibly have won the election without winning the popular vote.
Because it doesn't matter how many people vote for you (to a point), it matters
where they vote for you. And the number of counties is simply irrelevant for the reasons already explained.
I'm sorry you don't understand any of this, but there it is.