That was true in the TB3 era.

This will work just fine with a 40gbps USB cable.

Thunderbolt cables are slightly different, but are USB-C cables that support Thunderbolt alternate mode. Thunderbolt 3 uses a higher speed, 40Gb/s, that require tighter tolerances and special cables. There are also Thunderbolt 3 cables that are out-of-spec for USB 3.1 Gen 2. I think can use Thunderbolt on USB3 cables at slower speed.

USB4 unified them, making 40Gb/s standard speed and adding faster speeds. It is still confusing cause USB4 doesn't have to support Thunderbolt 3. Also, USB4 tunnels USB, Displayport, and PCI Express so there is no Thunderbolt alternate mode.

What's a USB cable if not a cable with USB connectors on each end? No industrial consortium is going to tell me what to call my cable.