“Because Xbox mandates that any games launched on its current-gen systems run smoothly on both Series X and Series S”

So no, they don’t get to just pick the minimum specs they support like on the PC version. They have to build a game that runs similarly on S and X, or not launch on either. Hence, the S is always going to limit what devs will be able/willing to do on the current gen consoles. More so than if they could just focus on the X and PS5.