It is correct. Speedwise, they should be classic USB 3.1 (5 Gbps.) Don't know if there will be degradation or not. However, as you can see on the digram, they all home-in to Ryzen APU, not thru a separate hardware hub.
Don't understand, there is no USB hub on that SBC, unless you are talking about using an external USB 3.x hub.
sure as old USB 3.1 is USB 3.2 Gen 2×1 nowadays, according to USB - Wikipedia sorry forgot the mentioned that, I mean the external USB-C HUB | UDOO Shop
what add confusion is that Embedded Processor Specifications | AMD lists: so my guess would be based on my list: 1 - 4: Gen2 5: Gen1 6: 2.0
Just checked the details using "USB Tree View". All these 4 exposed ports (two type-A and two type-C ports) are USB 3.1 Gen 1. That is, they are all 5 Gbps ports. Don't ask me why (BIOS, hardware, ... whatever reasons.) Good news is there are not too many USB 3.1 gen 2 devices (new Gen 2 devices came out only recently) and the actual bottleneck can be the NAND memory or SSD thenselves anyway. P.S. my SBC is BOLT, the original version, from the Kickstarter campaign