Television

I would argue the opposite. Good anime has 2 or 3 seasons. If it takes more you hit this dbz, Gundam, or One Piece never ending filler trainwreck.

Tell the story. Don't wear it out. Even if it is a little bit forced or contrived, at least it has a tolerable ending and direction to get there. There are still flaws, but it is concise enough I can deal with it.

Cowboy bebop, big O, paranoia agent, Fooley Cooley, death note, basically the whole of the adult swim line up excluding Inuyasha is perfect in showing that you don't need five plus seasons to build an iconic anime series. Are they flawed in their own way, yes. But they are brief enough to maintain their story and relevance and become mainstays.

Bonus points to blood plus that lasted a bit longer but held itself together the whole way through.

Hindsight, I may just be a sucker for the early 2000s and 10's cartoon network anime. But damned if it wasn't good.

Attack on Titan waited too long for Season 2, which was a huge let-down. You had to really believe to watch Season 3 after waiting four years for a short season that was not very good, and then they had the gall to come back again. Of course, season 3 came out swinging, and in retrospect, season 2 wasn't that bad, it just wasn't worth a four year wait.

The ones that are too short are Tokyo Ghoul and The Promised Neverland. Still waiting for a second season for both of those. (That actually adapts the source material, I mean.)