While I don't value verisimilitude in the same way you do, I am a stickler for framing site-based exploration as realistically as possible.
If there's biological monsters, the players can find their food source, their water source, their resting places, scat and refuse, etc. If it's a site where people used to live, you'll find bedquarters, living areas, items of leisure and distraction, their bathrooms, etc.
Magic items found via site exploration will be the types of magic items that the previous inhabitants would have logically had. Not everything, of course, because people living realistically will also occasionally collect random stuff serendipitously, just like the PCs do.
Ironically, I find that it is in fact possible to pursue "verisimilitude" so aggressively, you actually break through the other side and it becomes un-grounded again because, to quote Robert Herrick, "Do more bewitch me, than when art/Is too precise in every part." Everything placed perfectly, just so. Everything neat and tidy. Dwarves only have dwarf things, and you'll 100% always find dwarf things anywhere dwarves once lived, even centuries of looting later. Clerics only have cleric things, and you'll 100% always find cleric things where clerics once presided, even centuries of looting later. Etc.
Real life is messy, and real death is messier still. Many times, civilizations have risen and fallen in the same places, using and re-using the same materials (if not necessarily the buildings that made them.) The Athenian Parthenon stood for
over two millennia before being destroyed for stupid, stupid reasons, used for a variety of purposes over the centuries: temple, church, mosque, gunpowder depot (which is what finally killed it). Bronze from ancient times is rare in large part because people would melt it down to cast something new out of it. (There's actually a HUGE treasure-trove of ancient lead recovered from a sunken shipping vessel that is of enormous scientific importance, because smelted lead sitting on the sea floor loses its radioactivity, and is thus
incredibly valuable for ultra-sensitive radiation shielding.)
Sometimes, there won't be any axes or warhammers left in the ancient dwarf-forge because it fell to invasion and all the actually "good" (read: dwarf-favored) weapons were in warriors' hands, out on the battlefield, and got carted off as spoils of war centuries ago. Sometimes, a temple was abandoned by its priests because they moved to another site, and would not have been so careless as to leave nice things like holy symbols and fancy armor just lying around. Nearly always, societies have multiple different subcultures, who have different values and priorities, and it's a pure crapshoot what parts survive unlooted and undamaged for adventurers to pick up in the present day.