Pokemon anime was always tightly controlled and repetitive.
The only reason why gen 1 wasn't repetitive was because as I already said, anime got launched already half way into the generation cycle of the games, and gen 2 was already in the pipeline.

Though my theory was that they expected gen 2 games to come out much sooner back then, but it kept getting plagued with delays, which is why they added in this whole Orange Island part, because just adding fillers before the league wasn't going to work anymore, but it's just a theory.