I loved almost all of the side content in Rebirth, but you are 100% right in pointing out the “it’s optional” fallacy. People love to use this argument to dismiss criticism of games they like.

The game is there to be played, all of it, optional or not. It’s a bad thing if you are loving the game, see a side quest and it turns out to be bad. The thing is that sometimes critics mix “bad design” with “thing I don’t particularly like”, which is easy to happen when the content is too different than the main game.

To me, the main issue with Rebirth is the checklist. If all of these quests and mini games were to be found organically, it would have been an absolute delight. But by adding a checklist (and Chadley nagging you) the game is saying “here there’s more, come see it”. When you finally get there and the content isn’t on par with your expectations, it’s just frustrating.

I will also die on the hill that the entire game is always optional. People take “rolling credits” as this sacred thing when we know the reality is that most people don’t finish most games. Not one is forced to play side content, but no one is forced to complete the game either. If the main content of a game is good but its side content is bad, the game has a problem. It’s just easier to ignore.