From an outside perspective Trump was a shit show.
I don't really care about your internal politics, but what I can say is that he had a massive impact on America's credibility in the world. If you can just leave and rejoin the Paris climate agreement or unilaterally end the Iran nuclear oversight program, why should anyone really trust you on anything?
Joe Biden did a lot to repair this loss in trust, but it's hard work and will take longer than one presidential period. Much longer than it took to damage your credibility in the world.