M1 USB 3 speeds with external M2 hard drives

Looking at the specs for both M1 and Intel Macbook Pro they both state: Usb 3.1 Gen 2 (up to 10 Gbit/s).

So I don't think they support USB 3.1 gen2 2x2 which is 20gbit/s.

Thunderbolt 3 can do 40gbit/s but that requires a Thunderbolt nvme enclosure.

Hi, Yesterday also we test external ssd usb 3.2 disk too, we test it MacBook Pro 16, 2019 version and new MacBook Pro 13 M1, also we see same , all new MacBook m1 devices speed %30 less than old version. Our test result. Is (MacBook Pro 16 = 985mb per second read and 975 mb per write, ) same ssd we try (MacBook Pro 13 m1 = 675 mb per second read and 670 mb per write speed) after this I try also met friend new MacBook Pro m1 too, its same result, my idea is its not hardware problem its new Mac OS (big sure kernel still working old x64 code base kernel code, I hope they will do new update and they will solve it )

I tested a samsung ssd on M1 and Intel Air. On the Air system report shows the ssd as 10gbs, on the M1 its shown as 5gbs. Performance is obvioulsy affected. Apple support had no knowledge of the issue. Anyone else with this issue?

I also have this problem but with a different m.2 drive. I get approx. 550MB/s instegade of approx. 1000MB/s(the drive is faster but the enclosure max out at 1000 since its usb 3.2 gen 2

same issue here, I've got an nvme enclosure rated to 20gb/s and ssd installed with up to 3000MBps r/w and on the Mac mini m1 I only get 800ish MB/s