The nature of problems is different, but fundamentally the two questions of "how to distinguish between 1 and 0 in the presence of noise" and "can the reciever and transmitter change state fast enough" apply.
Optical PCIe would be hugely handicapped by lack of a standard optical PCB construction method. You'd have to print waveguides onto the PCB. And then it stops working if you get dust in the socket.
Optical PCIe would be hugely handicapped by lack of a standard optical PCB construction method. You'd have to print waveguides onto the PCB. And then it stops working if you get dust in the socket.