Turning that off is not currently an option, or planned. But that's interesting feedback.

On one hand, removing a core mechanic that we built the game around, including the gameplay, the world, and the story, kind of ruins the story and experience we're trying to create.

Without needing to look for food, clean water, etc, the game has no core loop. Removing it is basically taking away the central part of what you do in the game. Imagine removing food from Don't Starve. I mean, it's literally in the title ;)

On the other, I understand the accessibility angle completely. We already made permadeath optional, for the same reason.

So, never say never. However, as a key part of the game we'll need to look into it pretty carefully.

edit: sorry, missed the second half of your question!

The goal of a typical gameplay session is to escape the city. You start with almost nothing in a procedural world. What you find in the world will be different each time you play, but there are challenges that you will need to overcome to win. Initially (and throughout the game) you'll need to find food/water, but gradually your focus turns more towards crafting better weapons, clothing, devices etc.

The game will also have a narrative, but only the introduction/prologue will be present in the Games in Development version. Everything else will come on 1.0, when we're confident that it's a great experience. You guys are hopefully going to be part of that great experience, because the narrative just layers on top of the core game. By improving the core game, we'll improve the narrative playthrough as well.

Yeah that's likely to change throughout development. Right now yes, it temporarily suspends your hunger meter, but if you come down it gives you a bigger hit to your food meter than you might have experienced without it. But, if you keep taking Joy, eventually you'll overdose.