She is the first new main character in nearly 30 years, and the format is just very different now. The show doesn't follow a Pokemon League style progression or an adventure across the latest Region anymore, and is doing its own original thing.

Ash was on this huge, sort of linear journey competing for Gym Badges and exploring the world. Badges, tournament arcs, rival battles, easy checkpoints to follow like the games. For better or worse, people got so invested in this that we had huge meltdowns and news headlines over him.