>>25264485I think Ash's only evolved pokemon was Bayleaf. Totodile and Cyndaquil were jokes, Noctowl didn't do a damn thing, he ran around with a Larvatar that eventually just ended up going home to its mom, Pikachu was the only mon that did anything worthwhile.
Brock started gaining personality rather than being a once an episode joke, but it ultimately didn't go anywhere. Misty turned into Togeshit's keeper and stopped developing as a trainer, then got dropped at the end.
There was no rival to push Ash, and its arguable that he declined as a trainer and as a character, shortly after he just fucking won the Orange Island league and had some great moments with Charizard and his other mons.
It felt like they were too scared to replace Ash, but they didn't know what else to do with him so they just tried to repeat everything. Yes, that's the formula, but from Hoenn on they have him work with new characters and play with different ideas (contests, rivals, Ash as a mentor) to keep things fresh. Johto didn't bring many new ideas to the table and took away a lot of character growth and development.