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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Apart from the protocol technicalities everyone else mentioned, there is also the issue of voltage drop
If you pull 1 ampere via 24 AWG (~0.2 mm^(2)) wires, voltage drop will be about 0.085 volts per meter of round-trip distance, so with a 3 meter long cable you’re looking at about half a volt of drop
A 0.5V drop is pretty significant when you’re carrying 5V
On the other hand, Ethernet, for the most part, doesn’t carry much power, only just enough to transmit the signal
Unless you’re using PoE (Power over Ethernet), but if I recall correctly that is limited to 0.35A (meaning the voltage drop per meter will be about a third of what I said), and carries 48V (meaning you have a much larger margin of extra voltage you probably don’t mind if it’s lost along the way)
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