Third time: I'm not imposing some kind of prescriptivism, and I know that it's common. You're not bringing in any new information here. I'm saying it deviates from the usual pattern of using "the" when the noun has definiteness.
To repeat another part of my initial post, it's like the use of "the" in "the bigger they are, the harder they fall". It's clearly a different usage/meaning/sense of "the" -- in fact, most other languages use a different word for that sense. (German uses je ... desto.) It would be very dubious to explain all uses of "the" as "oh its when the noun has definiteness". It wouldn't cover that case, and it wouldn't cover (the typical use of) "I went to the store".
To repeat another part of my initial post, it's like the use of "the" in "the bigger they are, the harder they fall". It's clearly a different usage/meaning/sense of "the" -- in fact, most other languages use a different word for that sense. (German uses je ... desto.) It would be very dubious to explain all uses of "the" as "oh its when the noun has definiteness". It wouldn't cover that case, and it wouldn't cover (the typical use of) "I went to the store".