Do you have some concrete examples?

"Back-in-the-days" you'd click and stuff would instantly happen, and I don't remember anything being more difficult to visually interpret.

On my Kubuntu desktop if I disable all animations (the whole compositor) I don't feel there is an increased cognitive load of rescaning things - but maybe it's my preexisting memory of the UIs and certain baked in UI expectations. Maybe this animated stuff helps people that are computer illiterate? (software made for the lowest common denominator)