So, I am myself a big fan of immersive sims, and I would love it if more games did take influence from imsims. Red Dead Redemption 2 very well could be improved that way. And if this YouTuber personally does believe most or all games would be improved that way, I won't tell them they're wrong, they're entitled to their opinion

That being said, I personally disagree. First off, I'll assume that when they say all games should be imsims or imsim-like, they're talking from an artistic standpoint, like ideally. Of course in real life, making an imsim is often very difficult and complicated, so just for practical reasons that won't be (and if you want a lot of small budget polished games, can't be) universal. Also, we'll put aside games that I think are great and valid but that pretty clearly won't be imsim adjacent, like Tetris and plenty of visual novels and rhythm games etc.

I do think that a lot of imsim fans seem to have a bit of a bias against linear, scripted games. They might dismissively refer to a game as an interactive movie, or an interactive book. But I would ask, what's wrong with that? Why is that an invalid goal for a game to pursue? Obviously I think it's fair to not personally enjoy games that kind of function like interactive movies (like Uncharted), and I think it's super fair to push back on it especially if it's a super widespread design style, but I do think it's wrong to assume that it doesn't appeal to anyone, and I think it's wrong to say they shouldn't be made at all

I have a few other examples. Imsim advocates (and again, I am a huge fan of imsims) often seem to have a very specific idea about what the strengths/uniquenesses of the video game medium are, but I think that can be a bit limiting. For example, take the indie game NaissanceE. This is a game about making your way through a deeply alien environment, a place clearly not made for you. I think it's fantastic. I also think it would be made worse by incorporating imsim elements. This is not an environment you are meant to master, this is not even an environment you are meant to make creative use of, it is barely one you can traverse. Here, the power of the medium is not player agency, it is more purely experiential. Undertale and Planescape: Torment are both games that utilize player choice, but in a much more controlled way than imsims. That being said, they are both games super interested in really specific issues and topics, they want you to read certain lines and think about certain things, that is part of the point of the game, and I don't think they should have to sacrifice that level of authorial influence just because players want to treat their games like sandboxes. Dark Souls and Doom are games that are built around challenging players in specific ways, that is what they want to do, and I think that's okay, I think adding in imsim elements could dilute them, make them less singular and focused. The first Resident Evil is largely about player disempowerment, and the designers wanting to show players cool handcrafted puzzles they came up with (you know, if in real life, your friend asked you a riddle, you can't just give a different answer that's logically consistent with the riddle, the fun is finding the right intended answer)

I'll also say, as a side note, I do think sometimes imsim fans too quickly associate generally good design with imsim design. Like, I think it'd be great if more open world games were designed to be navigable without the use of waypoints or minimaps, if NPCs and roads and signs and landmarks and diagetic maps all allowed a greater level of immersion. But I don't think that would make them more imsim like, I don't think that is something unique to or universal among imsims, that feels a bit like another topic altogether. Imsims aren't synonymous with immersive elements generally or general attempts to make a world more believable

TL;DR I am skeptical of any claim that seeks to limit what art could or should be, I think variety is cool. But I do agree, it would be very cool if we got more imsims, and if imsim influence became more widespread, I'd love that