It's been four years of continuous Trump bashing.
I don't think that makes much of a difference to be honest and isn't really part of my considerations. He got a load of media bashing during the last election and new stuff kept coming to light (like grab her by the...) but it didn't do anything. I think his supporters (and some others) aren't too bothered by that. There haven't really been any shocking revelations in the last few years for Trump.
I think if the election was this time last year he would have won but people have been unimpressed by how he has turned the Covid crisis into an opportunity to promote himself and how he has attacked scientists, mocked mask-wearers and social distancing and so on. I'm a sceptic myself when it comes to a lot of the government intervention here in the UK but I think it's about attitude and leading by example. Being macho has worked on other issues and helped him beat Hillary but I actually think people trust and respect Biden a lot more for taking this seriously. This is just my POV as someone from the UK though.
I don't want to get into a long debate and I know Yoda said to avoid actual political debate but I don't think he's really delivered much either, to be honest, at least not in the conventional sense that I would expect from a Republican. Economically he hasn't been very fiscally prudent, with a lot of his barriers/tariffs damaging, his libertarian war stance seems to come and go when he wants votes, there's no wall and so on. He's very authoritarian and anti-free market (like trying to censor Twitter too). I think a decent Republican would beat the Democrats who have a lot of potential weak spots (court packing, law and order), but they picked a safe moderate candidate hoping people would go for the calm option.
But back on topic the polls would have to be a lot more wrong than last time for Trump to win as I understand it. Last time they actually seemed to slightly underrate HC on the Popular vote, and Trump just managed to get like 2/3% more than predicted in some key swing states. If Biden manages to hold on to what HC got and add a few more then he gets it. Again, this is my view from afar but I do take a keen interest in all this, but I would really be shocked if Trump won again.