Nearly all of what Trump can claim credit for is not things he has done intentionally, but what he has done unintentionally, and which we can almost thank him for.
We can thank him for rising our awareness that if Trump were even 10% -20% smarter, he would the US in a civil war while threatening to launch nuclear weapons on any country who ticks him off. Imagination what it be like if we had elected Putin to be the president of US. We can credit Trump, in a manner of speaking, that he is dumb as a rock. If he were smarter, he would have a strangle hold on US that would require over throwing him by force to remove him from power. If Putin were elected president, he would never step down, and several political rivals would have already disappeared never to be seen again.
I do believe that Trump will lose the 2020 election and refuse to accept the results, and even might try to find a legal reasons to try get the SC to throw out the results, but in the end, he will legally be forced out of office. Sure, he might spend the rest of his life claiming the Deep State controlled the election, but he will do so as a powerless ex-president that nothing more than loud mouth on Fox news.