DnD has often been portrayed as appealing to the kind of nerdy rules-lawyers that like to argue
Not a totally unfair critique, but also not unique to D&D.
I’d say the bigger issue tends to be around certain players feeling creative or desperate and trying to lean into the plot/setting with less respect for the rules. So, for instance, “If I can’t move the big rock with a Strength check alone, can I get some ropes and set up a pulley system?” <throws a bunch of math at the table> “See? This should give me a 3x multiplier to my Strength, so I should be able to move it easily?” And the DM just looks at that, shakes his head, and replies “All that’ll do is give you Advantage (and if you move the rock you’ll derail my plot)”.
But more broadly, I’d say the problem with D&D is that it’s inevitably the same Medieval High Fantasy setting in one way or another. The format of the game is geared towards the classic Journey to Mordor, with challenges and story beats and pacing to match. It doesn’t play well with modern settings, because modern and futuristic technology tends to trivialize magic (especially under the Vancian system). It doesn’t play well with the Horror genre, because the game rewards “winning” rather than “survival”. It doesn’t play well with PC antagonists/betrayers as the class system puts you at a huge disadvantage when you’re not working as a team, so heel-turns and dramatic reveals can leave players with a sour taste in their mouths in a way a game more explicitly geared towards Finding The Traitor does not.
But DnD is in the unique position of already having proven with 4e that it can nail down a rigorous set of principles and a style guide that leaves ambiguity behind, courting a whole section of RPG players who desire that, and then retreating from that position with a new, fuzzier, system document.
As I understood it, 4e was an attempt to bridge the gap between the strategic tabletop genre and the D&D style of play. It was a kind-of Return To Chainmail, with this whole vision of the game really going back to these very grandious geographical set-pieces and large army combats, with the heroes playing as champions of great armies rather than rag-tag murder hobos. Very much inspired by Warhammer and Warcraft.
5e was more of a back-to-basics dungeon crawling game, keeping the streamlining of 4e but reintroducing a lot of the customization and flavor of 3e/2e/1e.
But they were still ultimately board games in practice. Positioning your models to flank or ambush or avoid a fireball remained a pivotal part of the game. Hell, the very act of flinging a fireball or swinging a sword to resolve a conflict was a fundamental cornerstone of the game.
Compare that to a game of Vampire or Call of Cthulhu, where a lot of the story is about investigating a conspiracy and surviving when you are surrounded by people who want to kill (and very likely eat) you, who you cannot trivially club to death in response. That’s the real bridge that you have to get people over. This idea that you’re not going into the spooky old house to simply loot it and bludgeon to death everything you find inside. The idea that you’re not playing in a world where Good Guys and Bad Guys are these equal-but-opposite forces clashing together along a territorial border. The idea that magic isn’t natural and meddling with these kinds of arcane forces comes at a terrible price.
Nevermind how the character sheets are all topsy turvy and new players - especially players coming from D&D - simply do not know how to build/play a character that isn’t geared to punch every problem directly in the face.
Why is this a “problem” for DnD specifically?
It’s a problem with any game that abstracts away reality in favor of dice and event tables, but still expects the players to Theater of the Mind their way through the abstractions.