Out of the loop

From what I can tell, it's a juxtaposition thing. Many of the other shooters used in memes have stances that appear outlandish, and have gear that looks a little strange, almost trending towards ridiculous. The man you're referencing, Yusuf looks incredibly casual in comparison. His stance is at least recognizable as a shooting stance (even if it's almost appears too casual), his hand is in his pocket, and he isn't visibly using any of the gear that many other shooters are.

I haven't kept track very closely outside of the memes, so I can't comment on Yusuf's performance in comparison to the others, but the memes paint his character to be someone that gets the task done with minimal resources, where the others are given the role of a "tryhard" for the sake of the meme.

Evidently the imagery of these competitive shooters resonated with enough people that Lemmy had a small breakdown, but I always love to see my Lemmy feed trend into one topic for an evening or two. We all remember the beef stroganoff incident.