Musing that touches on rules, verisimilitude, realism, what the characters experience in the world, and not wanting to change sacred cows that make D&D be D&D...
Hit points. How have no PCs or NPCs in game figured out that "living beings" are essentially spirits whose essence is always trying to flee with an invisible forcefield holding them in the material world? I mean, they are just fine (with no ill effects) as long as that forcefield has even 1/total up - but the minute it passes the crucial level they are unconscious with it flickering and are in imminent danger of vamoosing within the next 18 to 30 seconds (and if they fail to flee it is still flickering for a while). How does that affect the view of "healing spells" when they actually just recharge force fields? Do the fact that there are healing potions (that recharge the field when taken "internally") mean that the forcefields are generated by the bodies? Or are they generated by the spirit-body interaction (is that why the forcefields usually have something physical inside them - because they need to)? Does being a minion merely mean one has the weakest possible force field? How does this change how animating undead is viewed - is it that it's bad to give things that don't have their own forcefield one? But why doesn't that apply to golems? etc...
Is it conservatism that has kept hit points as this great not-meat/maybe-luck/who-knows thing and stopped any of the rules (like 3.5s vitality and wound points) that would give them even a smidge more of a realistic veneer from really taking off? Or is it just a gameist price even most would be realists are willing to pay to make the game flow, and that adding anything else to it makes it too much for too many? If 6e made the default something that had wounds after a point would the revolt mostly be from older players or newer ones?