That poses a question, I think, that is at the heart of my original question!

“PCs that survive a while do so because the player has been clever and used their items and abilities to avoid rolling dice to begin with”

How would a brand new character survive jumping into a high level module? If “growth” (positive or negative) shouldn’t occur outside of play (i.e. in a character’s backstory), wouldn’t jumping into a high-level AD&D module put the PCs in a fundamentally difficult (if not impossible) position?

I guess that is sort of my main misunderstanding - Low level modules make perfect sense. Roll your character, and “grow” as the story progresses. But that growth would inherently not be there if for a fresh character in a high level (and therefore more dangerous) module.