2016 was very different. He got a lot of coverage then, but it was very much of him being on the front foot, attacking people in crude ways etc. Now all the coverage will be him on the defensive. It’s all whining, which takes away from his strongman persona.
Also, in 2016 he had an actual platform (build the wall, drain the swamp, etc.). What is his platform now? He has the disadvantage of already having been in office, where he didn’t deliver what he promised, as this business man who could fix Washington.
All this means nothing to his base, but it will to independents, and maybe even ‘normal’ Republicans. His best chance is low turnout through voter suppression and/or Biden regressing significantly in cognitive ability.