If he had acknowledged some version of her story right away.  Something like "I do remember something with Dr. Ford back then, I believe I may have misconstrued the situation and if I did do something she deemed to be inappropriate or too aggressive as a 17 year old boy then I own it and I apologize sincerely to her.  I have dedicated my adult life to being a good husband, father, co-worker, boss and judge and I believe my demeanor can be vouched for by anyone who knows me."

Then the Dems could have come up with some other way to discredit him and we could be discussing that!

That would have simply created screams of "UNFIT!" and they'd have turned to slandering the next person. In this situation, everyone's just playing a game to get what they want. Since that's the case, it's perfectly rational that you don't give either side a single opening, ever, because that'd be the end of it.