Yeah but Fallout is much more of a 'hardcoe' game. It's atmosphere is a lot different to TES, what with everyone struggling by in life, radiation, dehydration and starvation facts of life, and mutants crawling around the wasteland, so it makes sense to have a hardcoe mode. This is just a fantasy, open-world game.
Eh?
TES, where everyone struggles by through bandits, creatures, undead, Daedric Princes (and not just Ser Mehrunes, in all his attempts), transcontinental invaders, massive plagues, environmental threats (depending on province), Governmential and religious conspiracies (was it Tiber, or Wulfharth, or Arctus that made Talos again?) and other raw facets of existence.
I do see the distinction you're trying to make, but I still find it's a rather arbitrary one at best. A game series can be as 'hardcoe' as the designer wishes to cast it as. Hence in Daggerfall, gold had weight and everything could cut you in half at level 1. And hence in Morrowind and Oblivion gold was weightless and for the latter of those two, by comparison to Daggerfall and the former of the two, everything died at the sight of you at level 1. None of which had any relevance to the grit of the particular environment; Daggerfall had far more civilization than either Morrowind or Oblivion. And yet it still represented those hardcoe elements, quite nicely at that.
In addition what kind of weight are we going for here. If you want a very expensive object do you need to drop everything to buy it to carry all your gold? Is a weak mage character able to buy an expensive item? Or do you end up with banknotes and a cash economy once you have deposited your money into a bank?
Personally, I would prefer the weight of gold to be more on the minimalistic side, such as 0.03 or 0.05 units per gold piece. The idea (for me at least) is to make any gold in the thousands start to get cumbersome, as well as eliminating the ludicrosity of trekking around with a king's fortune in one's pocket. Once the thousand-mark gets hit, that's when bank notes would play a part.