Why are people acting like another Trump administration couldn’t possibly have any lasting consequences, when we’re still dealing with the aftermath of the Reagan administration now.

Because people (in general) have a really hard time even grasping the concept of “lasting consequences.” If something’s wrong with society, the most automatic response seems to be “blame it on whoever is in power right now this minute.”

(And not whoever has the most actual power, either. Often a symbolic figurehead.)