Optical PCIe 7.0 connection hits 128 GT/s

So I guess what this makes me wonder is: Why are we using electrical signals to connect the data lanes between components and computers these days, rather than moving everything to optical for data movement (obviously power would stay electrical, but that's already on separate lines)? I assume there's an element of cost, and once the photons get where they're going they have to be turned back into electrical signals to actually be used until such time as we get around to getting pure light based computers working (someday but not yet...), but that must not overwhelm the advantages or we wouldn't be looking at this being developed.

> I assume there's an element of cost, and once the photons get where they're going they have to be turned back into electrical signals to actually be used until such time as we get around to getting pure light based computers working (someday but not yet...)

You got it. We can't make optical transceivers as good as electrical ones. Not as small or power-efficient.

They require significantly different fabrication processes, and we don't know how to fab them into the same chip as electrical ones. I mean: you can either have photonics, or performant digital (or analog) electronics.

We've gotten really, really good at making small electronics, per the latest tech coming out of Intel & TSMC. We are... not that good at making photonics.

> We can't make optical transceivers as good as electrical ones. Not as small or power-efficient.

I was under the impression that for 10Gb and above network transceivers, optical SFPs weren't getting as hot as copper ones. Is that difference related to something else?