The wire speed may also refer to maximum throughput, which typically is a couple of percent lower than the physical layer net bit rate in wired networks due to data-link-layer protocol overhead, data packet gaps, etc., and much lower in wireless networks.
Network switches, routers, and similar devices are sometimes described as operating at wire speed.
Data encryption and decryption and hardware emulation are software functions that might run at wire speed (or close to it) when embedded in a microchip.
The wire speed is rarely achieved in connections between computers due to CPU limitations, disk read/write overhead, or contention for resources.
However, it is still a useful concept for estimating the theoretical best throughput, and how far the real-life performance falls short of the maximum.