The issue is manifold:

  • There is a large secondary industry that has emerged around D&D that produces content out of and for D&D. This includes third party rules and adventures as well as transformative content like actual plays as well as gaming video essayists and so on.
  • The most visible parts of this industry are the actual plays.
  • There is a clear financial incentive in using D&D for actual plays, because actual plays using other systems do not draw the same crowds as actual plays using D&D. There is no nefarious intent at play here, it's simply financial realities at play.
  • However, these people may wish to obfuscate those financial incentives and present them having arrived at D&D as coincidental. Since a lot of actual play content eventually wants to branch out from dungeon-killing fantasy monsters, this creates tension with the game mechanics.
  • What this creates is a lot of talk about how the fact that D&D chafes against this type of play is either a non-issue that can be fixed by the GM or actually inherent to the very medium of TTRPGs as well.
  • A lot of people are coming into TTRPGs with an a priori understanding of the medium like "it's okay that TTRPGs (D&D) can't handle all types of situations, the real power of TTRPGs (D&D) is that they can be modified by the GM on the fly."
  • This creates tension between these people and the people who actually think tabletop RPGs are worth engaging with as texts taken at their own word as well as the people who have a vested interest in their tabletop RPGs being treated as things worth engaging with on their own terms and not just as lesser versions of D&D.

Again, there is no nefarious intent at play here on any side, but it's simply in my personal interests to engage with RPGs as texts. Because the aforementioned cycle feeds and repeats itself and it doesn't actually result in a lot of interesting and good and cool new design. it just leads to more D&D with different numbers.