And that seems both an understandable observation, and a weird thing to be grumpy about. Sometimes it’ll be narrowly about something that only makes sense in the context of D&D, like how classes or alignment work. Sometimes it’ll be more substantive.
But… it’s a game that’s, like, 50 years old or nearly so. It is in its fifth edition, and there has been a constant stream since the beginning, before the beginning! of iterating on the rules. The game began by bolting some individualism onto a wargaming ruleset, then, from my perspective, the idea that since it’s mediaeval in implied setting, let’s lean into that, and allow those individuals we have bolted onto our army game to do things as individuals that aren’t army things. You want to be Conan? Cool. You want to be Aragorn? Cool. You want to be Merlin? Cool. You want to be Bilbo? Cool. Let’s add some rules for that to really play those things up. Well now, since you’re Bilbo, maybe there’s a dragon lurking around here, and some talking trees, and look, I have this weird-looking plastic monster, let’s write up some rules to fight those things rather than armies…
And so it goes. Eventually, the individual characters weren’t bolted onto another game, they became the bulk of the game, absorbed the wargame rules, and after a bit of digestion, popped out of a chrysalis as a whole different game. To mix metaphors.
And from there it just kept rolling along, like that one video game, bolting on ideas, absorbing some, digesting others, dropping some, and adding onto itself. Of course this wasn’t magic, or undirected. It was the decisions of millions (?) of players over time, filtered through hundreds of writers & the copyright and trademark holders. Drama, sometimes, messy interpersonal relationships sometimes. HUGE egos from time to time.
So the game has always been a game about itself, even before it was really, in any meaningful way, itself. It has always been about bolting ideas onto the existing game to see how to do a thing some player wants to do. It has never, really, been a game about playing in a fantasy world, that’s just a part that got bolted early on that really dominated. But the game has always been about playing with the game to see what it can do.