You do realize that at least since Daggerfall they have used level-scaling in TES games right?
Yes, and the less scaling there was, the better the game.
So it rather prove my point.
"A world is not devoid of life, just because your level influence the level of creatures on first contact. Especially not when these creatures and dungeons have lower and upper limits. It won't matter if you enter a level 25-30 dungeon at level 5, sure it will lock at level 25, but you will still get your ass kicked."
Semantics aside, whatever this methodology is sounds ok to me. There should be places a low level should not go, but neither should the whole world be restricted, but rather, it should be challenging.
I do however, want to experience a sense of development in my character development, lol.
Leveled zones, I already talked about it. If it's a logical situation, then it's good and nice.
But if it's just to have "super warlord goblins" because everyone in this cave is magically level 25 (because it's, you know, an arbitrarily "level 25 cave" where everything that lives in it, from Supermegagoblins to Ultragigarats, is level 25 "just because", then it's just barely better than the more direct world level scaling from Oblivion.
Logically, certain creatures of even the same type, can have quite different physical abilities. Each creature in the game, can realistically have a small level range it can spawn in, to create a semblance of natural variance.
Yes, and it's both more realistic and more varied to have this range between members of the same race. Having weaker and stronger creatures, and not everyone at the same level, is good.
But this difference must always be true, and not be dependant of the player level. If creature X can go from level 5 to level 10, then I should always be able to encounter level 5 to level 10 of them (in the appropriate circumstances, of course, like maybe their strongest members are usually the chieftain of the tribes/broodmothers/etc.).
But if I only encounter level 5 of the creature X when I'm level 4, and only level 10 when I'm level 15... Then it's not about the variance in the same race, it's just dumb, raw scaling - and if the ceiling and the floor are apart enough to encompass a majority of the gaming situation, then you have something like
Dragon Age, which PRETENDED to have "moderate level scaling", and in practice was just EXACTLY like Oblivion, with 1:1 scaling for 90 % of the game (you just didn't notice as much because they weren't dropping daedric gear, but a look at the config files shown that in fact nearly every foe was exactly the same save for one or two abilities and the skin...).
I think OP doesn't recognize, that the game (Fallout 3 in particular) pretty much only scales Up to increase challenge, and doesn't scale areas designed as "High Threat" Down, just because the player found it earlier.
Where as Oblivion scaled every inch of the game, to match the player's level.
As said above, not only the "the creatures of this area are of this arbitrary level" is downright dumb and anti-immersive, but if the floor level of the zone is low enough, then it's much like if there was total level scaling. And this was the case in FO3 with, again, the supermutants, which started to appear VERY soon (as I said, I could see one and kill him from level 4).
So they just felt very "deleveled" right from the start, and didn't feel at all like the powerful foes they should have been. I expected to run from them until I was quite experienced. Big disappointment :-/