This is my "640K should be enough comment", but we've reached the limits of optical fabrication with ~2nm. And really, it is just smaller transistors. Yes, that glibly does a disservice to the process engineers making this miracle happen, but I can get excited about "look, smaller transistors!" only so many times in my lifetime. :)

> optics on silicon,

Yep! That and quantum and post VNeumann architectures. There's some weird shit on the horizon that I probably won't live to see in household products, but I don't think it will be be optical deposition by layer. It might, who knows, I"m officially talking out my arse now. :)