Using words like "loyalty" and concepts like "being worthy", really doesn't help to make the discussion fruitful.
Games are about entertainment. What KIND of experience you prefer should never make you more or less worthy, and loyalty should be completely irrelevant. But I know what the point is, and it's a good one. I just think words need to be used with greater care.
If you want to entertain the minority, you generally have to sacrifice something for the majority. If you try to please everyone equally, you will almost invariably fail.
This "hardcore setting" approach is one way to make it work, but it takes a HUGE effort to design a game so that balance is maintained throughout - or it takes truly clever design.
Looking Glass did it really well with Thief - because the core gameplay remained intact, no matter what difficulty you chose, and yet the higher difficulty levels provided just the kind of challenge most "hardcore" gamers are looking for.
But the larger in scope your game is, the harder it becomes to achieve this kind of thing.
I haven't played New Vegas, but it sounds like it might work as well. We'll see. Personally, I don't believe for a second it will be "hardcore" or "enthusiastic" enough to please me thoroughly as much as a truly "hardcore" Fallout would.
Also, though I'm quite the enthusiast - I never cared for games that annoyed me. I don't see the appeal of having to eat or drink, unless the game is made as a survival experience from the design document and up. I just want a game that makes me think and gives me a lot of hard choices - things like that. Hunger/thirst almost always strike me as superfluous elements that get in the way of a great experience. It's a balance thing, really, and depends fully on the implementation.
Fallout would benefit from having "realism" elements like this, but it needs to be done well. Otherwise it might as well require me to go to the bathroom, or to keep clean to avoid infection, etc.