For my part I like how psycho history is like thermodynamics. Harry seldom is not predicting the future as much as tweaking a closed system’s evolution. The galaxy is huge and populated enough to be governed by statistics, yet estill limited to be closed system. The “Mule”? I know only the French name Mulet" does throw a wrench in the whole thing aka chaos. That is why there are two foundations the second one manages the unpredictable events.

As for the writing style well that’s a matter of taste, I love Asimov’s style but am not literate enough to explain why.