It has always seemed to me that the Impeachment has insulated Biden from these charges. Because they have been litigated, people, at least subconsciously, feel that if there was anything it would have come out then as a defense against the Ukraine charges. And they know that Trump wouldn’t have hesitated to bring stuff out if it was real.
Other people trust in Obama’s thorough vetting and 8 years of nothin. If there was anything then, they could have forced him off the 2012 ticket or stopped him from running. Even if they think there was a lost opportunity, people who had every reason to expose Biden didn’t-which is a capital offense in politics. Then there was the 20 plus opponents who didn’t bring out anything either.
So Biden is clean, clean, clean.