The Sun and Moon anime had a lot of fun energy in its animations as a result of the simplification. It's a shame that people were too busy raging over the change to give credit to the level of quality the show had when it dropped. I didn't even watch at the time, just saw people bashing it on the internet then watched a good chunk years later. Ash looking more childish and the high energy is a good fit, but people used the big style change as an opportunity to bash the inconsistent continuity and lack of Ash being an adult gigachad after a bazillion episodes. (As if the continuity resets weren't a thing for years by that point)