Inedible as in anything that isn’t food (ranging from something that would be dangerous, like glass, poisonous plants, or uranium, to something that is safe to eat but unpleasant with no nutritional value, like cardboard.) Eating the thing will be safe and painless.
everything in the galaxy would likely start drifting apart since there is nothing pulling them into this central orbit. some things would get closer to eachother and start attracting eachother and maybe they collide or start orbiting eachother. In the human timespan the sky would likely slowly get more and more “wrong”. at least that is how i imagine it would go.
well technically if Sgr A* were to disappear right now, we wouldn’t see any change for the next couple thousand years or so🤓