[spartanatreyu]

That argument doesn't make sense to me.

You can just choose to use light at a smaller wavelength.

Also, less density by itself doesn't mean less performance, the larger optical components can just run faster to end up with higher overal performance.

[dogber1]

In principle, yes, but: - lower wavelength light is harder to confine within waveguides (or transmissive optics), and messes up atoms when colliding (think of x-rays), - finding an efficient source at lower wavelengths is one of the main struggles of the semiconductor industry.