This is not to say that seasons after the first one are bad, but sometimes I feel as though later seasons exist because of the show’s popularity and not because the creator had more to say (The Last of Us, even though I love Part II). Also, it’s okay to have an open-ended ending with loose ends, leave it to our imagination on what’s going to happen next (Westworld).
It kind of depends on the story being told.
Some stories may set up some interesting ideas/concepts that could become good stories in their own right.
However there are things that are better left just being suggested and left to the consumer’s imagination, rather than outright explained.
For example, Yakuza 0 was a fantastic way of handling extra backstory stuff, especially for Majima’s side of things. It gave players insight as to why the wacky batshit character is the way he is through the rest of the series. It also gives insight into Kiryu and Nishki’s relationship, adding more weight to what happens in the first game.
I think a poor example would be the way that Metal Gear Solid V expanded on the Cobra Unit from 3. It explained that their previously unexplained supernatural abilities were actually just due to one of V’s plot devices. It took away from the mystique of leaving the cobra units abilities and replaced it with something pretty mundane.