What would happen if everyone thought this way. What if VW had, buried in their terms and conditions that emissions are the sole responsibility of the buyer? What if a restaurant had a tiny plaque obscurely displayed indicating that they were not responsible for food poisoning, intentional or not? What about all that nonsense that is going on lately with clauses for "fining" customers that write bad reviews?
That's quite a team of strawmen you've got there. And the thing is, some of those things you propose are both possible and true. Rules and laws involving cars are pretty rigidly enforced by laws. Restaurants can already do what you're proposing except no one in their right mind would ever draw attention to even the tiniest possibility that their food might be bad - there's way too much competition to even risk it. I'm not sure what exact thing you're referring to with the reviews thing but basically outside of anything protected by law you can sign away just about everything in a contract - the right to disparage, the right to participate in a class action lawsuit, and the right to talk about a product before a certain date.
Going back to the restaurant example, if a restaurant were to have a visible disclaimer people would go to their competition, all other things being equal. If you don't want to accept the terms of a pre-release Apple hardware product you can go to their competition. Apple TV just doesn't have any competition in the same spot (or at least nearly as popular).
You can scream injustice all you want but this is how things work in the real world.