USB 3.0/3.1/3.2 Gen 1 aka the kind that can do 5 gbps can only use cables up to 3m in length. Meanwhile Ethernet uses a similar twisted pair copper cable, but can do 10 gbps over 100m.
What gives, why is USB so limited in terms of cable length?
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USB was originally invented as a replacement for various standards (ps/2 , serial, firewire, parallel port) that connected small devices to computers (keyboards, mice, scanners, printers, digital cameras).
They tried to keep it relatively simple by having only two wires to receive and transmit data, and they designed the communication protocol in such a way that it’s important for bits to travel within some time frame across the length of the cable. Longer cables means each bit takes longer to arrive at the other end, so the host (the computer) could mistakenly think the device is behaving erratically or that it’s faulty.
Ethernet is more complex and uses more wires (at least 4 wires for 10/100 mbps, 8 wires for 1 gbps or more), and also uses isolation transformers at each end, and uses much more power to send the bits across the cable, and is less sensitive about timing.
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