I wasn't even a twinkle in my parents eye in the 80's so maybe that explains my atavistic attraction. (I'm using torches as a stand in for any mundane light source but of course torches feel the most fun - yes I know they realistically are not at all practical in an enclosed dungeon). But I dunno is it really just an 80's aesthetic? Peter Jackson's LotR? The Mummy? Game of Thrones? Lotta torches all over.
Edit: and this is to say nothing of pre-80's torches. Need a full history of the torch in adventure stories.
This is a start, but not nearly comprehensive or analytical enough.
Yes it's an '80s aesthetic. You're not helping your argument by using two "counter-examples" from the turn of the century - about 25 years ago - The Mummy (1999 - and intentionally harking back to Indiana Jones in terms of visual design!) and LotR (2001). As for GoT (2012 - that's 13 years ago), they don't use torches in a very atmospheric way for the most part, because they can't do lighting that works relying on them. They're very much a Night's Watch thing and occasionally for drama in battles. Torches
existing, even being pretty common is different from them being an aesthetic, which is actually something your earlier post seemed to recognise pretty well.
What you're doing is essentially supporting my point - this is an older aesthetic that's completely trailed off in most fantasy and people aren't into.
You don't address the fact (and it is a fact) that most people's main points of exposure to fantasy outside TTRPGs are videogames and fantasy literature, and in both, torches are increasingly rare, especially ones being carried by people (which is very different from when they're fixed light sources, mysteriously pre-lit and mysteriously everburning). Whereas lanterns and magical light sources, which have considerable crossover, are extremely common in these - as the things people carry around in order to be able to see. In part just because torches are just really impractical in the situations D&D adventurers get into.
As for "any mundane light source", that doesn't really make sense because the things you said you liked about torches, that they were easy to put out (trivial almost) and atmospheric/dramatic don't apply to lanterns, and outside of games like Shadowdark (or games set in the iron age or earlier), basically no-one has voluntarily used a torch since the 1980s in fantasy RPGs when any other options are available. And what even is "mundane"? A bioluminscence-powered lantern with like a big glowing bug in it or something is as "mundane" as a torch if you mean non-magical (and again, nothing new about this - in EverQuest in 1999 glowing bug organs were a very common light source because they were brighter and lasted far longer than torches).
Torches are generally not an interesting or fun resource
outside of games that put a major focus on them, and D&D is both not that game, nor can it ever be that game
and be D&D in any sense that matters. Pick a lane - either you're a game about torches (and there are a bunch of them! Why not play one?) or you're D&D, which is a game where magic is trivially common
for adventurers, where possibly multiple party members know the Light cantrip (or something similar) from level 1 (do you want to change that?), and where in huge numbers of D&D settings (including the Forgotten Realms), Continual Light/Flame devices are extremely common, to the point where streets are lined with them in some cities (and again, have been for hundreds of years in Realmsfarian terms, given that there were 2E descriptions of such). You say you weren't born until after the 1980s, but it's funny because you appear to be proposing turning the clock back the early '80s or even before.