I didn't care for Ash's Johto team back then because they came across as weak replacesments for Ash's Kanto team.
Back then Bulbasaur/Squirtle/Charizard were viewed as staples of Ash's team, and to go from those 3 to what seemed like Pokemon who had worse personalities and were weaker battlers was a disappointment. Charizard's departure is what actually kickstarted the initial hatred of the Johto saga. I know a lot of people who originally stopped watching the anime because they used to say things like, "How could Ash get rid of his awesome Charizard?" and so forth.
Obviously this doesn't matter now, but back in the time Johto was airing it was a huge disappointment. Ash's Unova team is sad though, no evolutions for the starters and too many pokemon.