If followed, the game text for the 5e basic pattern entails fiction-first
Contrast DW's basic pattern
The way I see it, the differences lie elsewhere. So not so much in being fiction-first, but perhaps in choices like task resolution versus conflict resolution (although this isn't as guaranteed a divide as it can appear on surface IMO.) So we see GM describes world, versus GM describes conflict. Also and very palpably, distribution of roles.
Here is a comparison of my own. Edit: And I apologize if it comes across as flippant.
5e's pattern: blah blah blah - roll some dice - blah blah blah
In contrast that with the pattern found in other games...
Dungeon World's pattern: blah blah blah - roll some dice - blah blah blah
Burning Wheel's pattern: blah blah blah - roll some dice - blah blah blah
Savage World's pattern: blah blah blah - roll some dice - blah blah blah
Call of Cthulhu's pattern: blah blah blah - roll some dice - blah blah blah
Warhammer Fantasy Roleplay's pattern: blah blah blah - roll some dice - blah blah blah
Vampire the Masquerade's pattern: blah blah blah - roll some dice - blah blah blah
Forbidden Lands' pattern: blah blah blah - roll some dice - blah blah blah
The One Ring's pattern: blah blah blah - roll some dice - blah blah blah
On the basis of this comparison, we can safely conclude that they are all about "rollplaying and not roleplaying."
This is all to say that if you opt for such a broad comparison and/or cast such a wide net as the basis for comparison, then every TTRPG will be fiction first, but they're not by most people's understanding of the terms, which is why I don't find your comparison particularly helpful or insightful. Despite that and your comparison, however, 5e D&D is not conventionally considered a "fiction first" game by the hobby. Why might that be?
IMO, and others are welcome to chime in, the comparison ignores a lot of guiding principles, procedures, and play/design elements that are present and/or absent in supporting that fiction first loop. It also fails to understand what is meant by "fiction first" and how that interacts with rules in place. "Fiction first" amounts to more than players engaging in a call and response with the fiction that the GM frames.
Take for example your earlier bit in discussion with
@AbdulAlhazred about Jumping using a Strength/Dexterity (Athletics) ability check. How likely will a Jump ability check in D&D 5e result in HP loss or a debilitating injury like a sprain or fracture that follows from the fiction? The HP loss is more likely if fall damage is involved, likely from a failure, but that entails the GM consulting the mechanics of the fall damage chart. The consequences of falling are dictated by the mechanics of the fall damage chart. The fiction matters in-so-far as determining how much falling damage from the chart applies. Contrast this with other games. The fiction of the situation may dictate from the resolution (failure, success with failure, complicated success, etc.) that the character takes a consequence that bypasses usual stress: e.g., sprained ankle. Now that the consequence of "sprained ankle" is a real issue for the character in the fiction as well. And the future fiction of the game must take that sprained ankle into account.