Good.
Something the fatigue people seem to forget is that superheroes always have and always will thrive when the world is in dark places.
They were there to lift people up during the Great Depression and WW2. They're here to lift people up during Iraq, 9/11, Trump, COVID, etc.
If people want superhero fatigue to actually happen, nothing quicker would cause it than governments across the world being so competent and amazing that left wing policies cause the gap between rich & poor to loosen up and most people to be not only out of poverty but with no worries and peak happiness.
If people are actually happy and positive and don't have worries, there's little need for superhero escapism.