It's a big difference because electrical signals have to work so much harder to deal with the low bandwidth and signal/noise ratios available to them.
This is why the schedule for PCIe and similar electrical buses has lurched back and forth, as at times progress seemed impossible and then somebody got patents that made the next breakthrough possible (at high price.)
Note for instance that optical PHYs run at 400 GBit/sec but 10 GBit/sec is aspirational for the home. Thus any optic fiber service you might get is two orders of magnitude away from the best possible. Contrast that to LTE, 5G, etc. which are right at the limit.
This is why the schedule for PCIe and similar electrical buses has lurched back and forth, as at times progress seemed impossible and then somebody got patents that made the next breakthrough possible (at high price.)
Note for instance that optical PHYs run at 400 GBit/sec but 10 GBit/sec is aspirational for the home. Thus any optic fiber service you might get is two orders of magnitude away from the best possible. Contrast that to LTE, 5G, etc. which are right at the limit.