Yes, research suggests that the human eye does indeed register the difference when looking at an 8K resolution display. In fact, we could probably perceive the benefits of an even more densely pixelated resolution.
As we’re fleshy things, we can’t directly compare the power of our eyes and brain to that of a display, but it’s estimated that to create a camera with an equivalent resolution to our glistening peepers, it would need to contain 576 million pixels.
Considering 8K is a 7680 x 4320 resolution, it’s nowhere near as intricate as our eyes’ capacity for perceiving clarity.