I almost agree with you on the first part, except that the story is whatever happens to our characters. If they get eaten by a bear, then that is the story, perhaps it will serve as a cautionary tale to the next adventurer. If the monster encountered is ill fitting to the world, then I agree with you completely. I would be severely annoyed if my party was wiped out by a random group of Drow in the middle of a desert at high noon. Because sun hating drow running about at high noon is sufficiently out of character for the world that it requires narrative justification. However if I was hunting bear in a cave and a troll came up from behind and ate our minstrel, then there is not much to complain about as trolls are known to inhabit the mountains, are fond of caves, and probably eat bears. It was my own damn fault for not posting a guard behind us.
I think I understand your point.
About the troll and the bear cave, though: What is the story here? The bear, the cave or the troll? The main problem I have with wandering monster tables is that most often in my experience, they distract from the actual story. So if the story in your example is a cave in dangerous wilderlands and you are trying to make the danger an issue, then why add a troll to an already dangerous bear? Why not present just the troll as the dangerous opponent? Why is a roll on a wandering monster table neccessary here? If the story is the bear, that, for example, needs to be protected or something like that, all of a sudden the troll makes sense as a story element. Because now the heroes have to protect the bear. But again, no wandering monster table roll neccessary here.
What I am trying to say is that because wandering monsters are randomly picked, I find it very hard 90% of the time to see a need for their existance storywise.
In the Warhammer 1st edition Doomstone Campaign the heroes are travelling through a mountain range full of dangerous creatures. The adventure designers wanted to bring across just that danger of the environment. So they installed several combats with wilderbeasts across the heroes' track. In that way, all those creatures served a story purpose. No wandering monster table was neccessary.
As to the second you are missing my entire point. It's when you are confronting an unscaleable wall to the front while certain death persues you from the rear that the moments I'm looking for come from. This is when you find the clever way out, or use the solution the GM never thought of. And if you don't and you die, the purpose, the meaning of it is this: Adventuring is hard, dangerous work. Only the cleverest, the bravest, the luckiest should dare it. And those that try and fail shower glory on those that succeed.
Without that risk you might as well play Arnold, the heroic door-to-door insurance salesman.
I think I get your angle.
I like scenes like the one you are describing. And I have played them in all varieties of roleplaying situations. So I think the scene itself is not part of old-school gameplay by itself. What I do consider part of old-school gameplay, though, is your explanation for an incurring TPK: the players (!) were not smart enough and adventuring is dangerous work.
And this is the part that I do not like anymore. Because what is so exciting about playing a scene like this is the danger for your character. If that character dies, it is very anticlimactic and the scene will be remembered by anybody that I know not for the suspense, but the TPK, which nobody will laugh about. And it will not help them with their next characters, either. Because what are these next generation characters going to do? Go back to the same wall? Killing them off will stop play right there. And if you are true to your new character's experience and stay within that new character's state of mind, he will learn nothing from that experience of the old character, because he did not encounter it. The player does, though, and will be working outside of that new character's mindset when he is experiencing his own "I am at the wall" scenario. That, to my taste, is not a good thing.
Plus, how to make room for a sucky GM that will not accept some of the stuff the players come up with? Especially when playing modules that have a very specific solution in mind to begin with?
So, to quote 4E: to say "yes!" in situations like this and not expecting players to solve a scene based on their own but on their character's experience, I find is a more delightful way to GM. I think it more challenging for the player, too, because you really have to block out the stuff that is not your character.
I'm not saying TPKs are fun, I'm saying that it's more fun to escape from a potential TPK by using the players brains, rather than the characters "avoid TPK" spell.
I hate those spells, too. "Teleport without Error" comes to mind. Especially because those spells tended to make non-spellcasters look and feel weak and make encounter design more difficult at higher levels. But that is a totally different subject.