Biden won the nomination because he had capital from being Obama’s VP and he was the only, ONLY, democrat who could beat Trump. Trump is formidable as a politician because he is willing to do the things the others are not, in either party. That means things like race baiting and nationalism - things competent people understand are ultimately destructive. But Trump doesn’t care about anything other than Trump, not the country, not the election, just Trump and winning.
You think Joe Biden is so awful but he is still beating Trump in the polls. And if Biden gets us to almost any other Republican president than Trump then he did his job. If not at least he bought the country some time.