D&D hit point whittling - simulationist mechanic?

You know, go into a dungeon, some goblins scrape a few HP off you, you press on.

It's a stupid move, when you could just go back, rest up, return at full health. Smartest to go back and rest after every fight.

And I know, it jars to think of it!

But it's true.

So here's the proposition - that hit point whittling is essentially a simulationist mechanic - and I mean that in that it will draw you towards simulationism. Because gamism wise you are playing really badly, whilst at the same time you are stubbornly not retreating, fretting about your lowered HP and so playing right into the hands of emulating a certain genre. Simulating it.

Now on the other hand I have played in games where say there's a magical barrier and once you pass through it, you pass back - you have to find some other way to escape. Or you go through a portal and it deposits you somewhere and the portal closes behind you. In these cases (assuming you can't rest in the dungeon), I say and grant it's still gamism - losing a few HP here and there is a big deal. It's a death of a thousand cuts - and here's the thing - not a simulated death of a thousand cuts (as is the above example of pressing on with reduced HP - when you could just go back and rest), it's potentially a real death of a thousand cuts!

It's the thing to ask about your game - as you wander through the halls of a dungeon at less than full health, is is a frightening trek into the unknown, or is it a simulation of a frightening trek into the unknown, supported by a stubborn disinclination to go back to town and rest?