Season 1s are great, setup, some payoff, a bit of lead into the overarching story. Then season 2 to X. The heroes win and then lose in the final episode, cliffhanger to next season. People get bored. Final season is announced and they wrap up the show.
Even Supernatural has actual ending after 15 seasons
Ted Lasso (announced it would be three seasons at the beginning and stuck with it)
Succession
And like every good story oriented cartoon. We’re in the actual golden age for cartoons right now and more people need to take advantage.