Trump's going to lose to anybody. He's been that bad and most of his policies ( eg trade wars ) can only make things worse between now and the election. Now he's threatening to go to war with Iran which is insanity, another sign he's lost his marbles.
Could be, but democrats being arrogant and cocky may make them repeat the same mistakes as 2016. If out of the primaries comes some divisive or weak candidates, it will not be an easy path.