I think you are conflating things that aren't analogous. As such, we are probably at an impasse, debate wise. All I can say is as a professional freelance writer and designer, "specific monsters use specific traits" is game design, not lore.I disagree.
Here is lore: a body of traditions and knowledge on a subject or held by a particular group. Consistent lore is the reason D&D has grown in popularity. Lore is a cleric uses magic through divinity. Wizards can use transmutation. Specific monsters utilize specific traits. The level of technology. The cultures and traditions and appearance and abilities of various races. These are all tied to lore.
Put it this way: Lore is distinctly tied to setting (time and place). It is distinctly tied to inhabitants. Those two things, setting and inhabitants, help create a ruleset. The two are tied together.
Design Philosophy, while it could be tied to lore, is comprised of the elements and devices used to run the game. Do you want to use have wider variability? Use a d100. Do you want controlled outcomes? Use a d4. Do you want long, more "fantasy real" combats? Institute the design of combat math. Do you want short combats? Institute the philosophy of zero combat math. That is design philosophy, and it can adhere (and in my opinion) should attach itself to lore. But it doesn't always do so. And that is fine - to each his own.