Hadn't heard of this eGPU dock before, but it seems to support USB 4 as well. I wonder why they only mention USB 3. USB 3 is 5Gb/s, but USB 4 gets you to 40Gb/s, near HDMI 2.1.
I think that if the main goal here was speed, they'd just be using Thunderbolt instead of creating this solution that seemingly only uses regular USB3, and I'm very interested to hear how this works exactly.