It is unknown whether the ports are independent, or some of them or all of them are connected to an internal hub.

Even if they were connected to a single CPU port through an internal hub, if you used two 5 Gb/s USB Ethernet interfaces you would get close to full speed for them.

Having 10 Gb/s USB instead of the so-called "5 Gb/s" USB (in reality 4 Gb/s), provides much more additional I/O throughput than having 5 Gb/s RJ45 instead of 2.5 Gb/s. I agree that having 5 Gb/s Ethernet would have been nice, but it is much more valuable that it has 10 Gb/s USB, which is very rarely encountered on Arm-based computers.