Harris is worse than Joe. If you saw the debate on CNN Anderson Cooper interviewed her afterwards and asked her multiple times "is the Joe Biden we saw tonight the Joe Biden you see every day" She refused to answer, she got extremely bitchy with him too. People want to hate trump and say he is a mean tweeter, well Harris is a bitch and we'd be worse off with her.
Now to play devil's advocate here, anyone who is voting Biden is going to vote for him at this point no matter what silly thing he says or does next. Trump may gain more voters if there is another debate and Biden flops again but I certainly can't see Trump losing any voters at this point in time.