I think they mean USB 3.2 Gen 2x1, which does support 10Gbps throughput.
Apple's tech support page about their Thunderbolt 4 cable (https://support.apple.com/en-om/HT210997) also states "USB 3.1 Gen 2 data-transfer speeds up to 10Gbps".
I'm a little confused by Apple's machines wouldn't support USB 3.2 Gen 2x2 when they support USB 4 and Thunderbolt. I guess they couldn't figure out how to get faster USB out of their chipset? They list the same limitation on their iMac USB 3 ports (https://support.apple.com/guide/imac/take-a-tour-imac-apd2e7...).
> "I think they mean USB 3.2 Gen 2x1, which does support 10Gbps throughput."
They explicitly say USB 3.1 Gen 1 in the article, and the linked technical document [1]
> "I'm a little confused by Apple's machines wouldn't support USB 3.2 Gen 2x2 when they support USB 4 and Thunderbolt."
Yeah, it's weird, but Apple has never supported Gen 2x2, AFAIK. 2x2 means you have two 10 Gbps channels running in parallel on two sets of pins, but USB 4 does a similar thing to get 40 Gbps and they do support that. Shrug.
> "But why is the 16-inch MacBook Pro able to run USB 3.1 (10Gbps)?"
USB 3.1 Gen 1 is 5 Gbps, not 10 Gbps.
(My Thunderbolt LG Ultrafine 4K also has USB 3.1 Gen 1 ports on it, so I should know...)