I think you misunderstood what they meant. Like you said, your eyes adjust to have anything you’re looking at in focus. This means games shouldn’t use DoF because it makes everything not in the center of the screen out of focus. Our eyes can look at anything on the screen, not just the center. Until the game can track our eyes, not the center point, DoF is doing the opposite of what our eyes do. We can only look at one point clearly, instead of seeing anything we look at clearly.
I think you misunderstood what they meant. Like you said, your eyes adjust to have anything you’re looking at in focus. This means games shouldn’t use DoF because it makes everything not in the center of the screen out of focus. Our eyes can look at anything on the screen, not just the center. Until the game can track our eyes, not the center point, DoF is doing the opposite of what our eyes do. We can only look at one point clearly, instead of seeing anything we look at clearly.
I wonder if there’s a tech demo somewhere on the Internet of DoF using eye tracking
edit: huh yeah, here’s a video 18 years old. kinda neat https://youtu.be/HdW1v9TPNYw