Let's assume that every indicator is right and Democrats win control of both Houses of Congress - and that the new Congress is seated. I think that happens, but I can't say with 100% certainty of anything anymore.
We have a Trump Administration that has been engaged in a smash-and-grab campaign of thuggishness and graft. What's more is that Trump is already crashing out. What will he do if faced with a hostile Congress?
Trump is mentally unwell. Yes, he is not intelligent AND suffering age-related cognitive decline. Yes, he's an example of what happens to the emperor when no one says, "no." However, the narcissistic wound that he might be about to receive is potentially mortifying.
Trump was not greatly restrained during his first term, but he was mostly constrained. Now, he's surrounded by so many toadies and creatures feeding his id, that the potential for intentional harm is very real.