Don't be silly. Tolkien's works are definitely the kind of thing we'd like to emulate in a fantasy role-playing game like D&D, whatever genre labels you decided to apply.
Gygax disagreed. He included elves and such as a way to attract a segment of players he was interested in. He regarded Tolkien as a secondary influence, way down on the list from Howard, Leiber, Vance, and so forth.
And Robert E. Howard's works are similarly full of "high-level" characters dying with a single stroke -- just not the protagonist.
All the examples I can think of are wizards. Assuming Conan has 1d6 sneak attack from his years as a thief, and power attack, there is no problem at all protraying those scenes in D&D 3e or Conan d20.
No, you can't really, because Smaug was in no danger and he clearly knew he was in no danger -- until he got hit by Bard's Black Arrow through the chink in his armor noticed by Bilbo, overheard by the Thrush, and passed on to Bard.
Smaug is described as an old and pretty worn out dragon. You could say he has 30 hit points and DR 10/magic. Maybe Bard is a Pathfinder charcter with Penetrating Strike and Deadly Aim. One critical hit, one dead dragon.
Agreed, but that doesn't mean that hit points have no inherent character as a mechanic. They intrinsically make it difficult, even impossible, to have a character vulnerable to a single arrow but not guaranteed to die by four or five arrows -- without lots of additional rules to bypass them.
Howso? All that is necessary is that the single arrow do enough damage, and that the four or five arrows not do too much. I think the problem you are describing is actually MORE of a problem with limited hit point systems, like GURPS, or some kind of more abstract system, like True20, where every hit is a chance to fail a saving throw.
If you want PCs to be able to stagger around with an arrow in them and still fight, you are basically looking at some kind of hit point system, or something along the lines of HeroQuest