Ruin Explorer
Legend
LotR is BUT it's not really something people draw their own characters from much, if at all, even for my generation.Tolkien would still be out there, and still be in the public consciousness. It may not be as different as you think.
For starters, I dunno if you noticed, but a lot more women play RPGs now, and Tolkien has approximate zero valid female characters, certainly zero adventurers (and no Arwen doesn't count and Eowyn isn't even close to counting). So that's like 30-50% of your players just right out the door right then. (Honestly LotR is way more of a sausagefest than Le Morte D'Arthur which really an achievement).
Second off, LotR doesn't have many characters that match up well with D&D classes. You've basically got... Fighters. That's it. Maybe you could make an extremely stretched case that, technically, Sam is a Paladin. It's cute but it's a stretch. The hobbits don't do Rogue stuff, really. Aragorn doesn't do really any Ranger things. At all. Gandalf doesn't even really do much Wizard stuff. Hell most of the Fighters don't even do Fighter stuff.
It's a fun set of movies (yeah I went there) but apart from a small percentage of people going "I'm going to make Legolas" before realizing D&D 5E doesn't support that all that well, that's basically got no impact (Legolas' haircut has had a profound impact on elven haircuts in like every game though I'll tell you that).
Compare and contrast with anime or video games or fantasy novels or fantasy TV shows and cartoons, all of which are vastly more diverse not just in male/female/other, or non-white ways, or disabled/able ways, but also in the simple sense that they have more different characters with different abilities, and way more of those characters have the sort of flashy magical powers most D&D characters have, and way more of them do fantastic stuff with their abilities. They also act, look and talk much more like most D&D characters.
And why do these characters have those powers and mannerisms and so on? BECAUSE OF D&D. We're on like third generation of a feedback loop here! Almost all of this stuff exists or portrayed the way it is because of D&D. Not because of Tolkien. Because of D&D. And thus it's much more relevant to D&D than a series of novels that basically only influenced D&D in any major way by putting certain races into the game. And they've been there for decades now, so their origin is almost irrelevant. They're D&D races.