Admitting he’s been intentionally and willfully lying in public for years is politically bad for Trump.
I wish I had your optimism. I don't think it matters, as someone in the right-wing spin-sphere will come up with some viral explanation that they'll just adopt. All it takes is just one person coming up with something they can accept.
As he said, he could shoot someone on 5th avenue and these rubes will still support him.