USB 3.1 cable transferring 40MB/s

I have a WD Passport SSD with usb 3.1. With the stock cable I transfer data at 380-420MB/s. (Limited to SATA)

I purchased a 10 foot usb C 3.1 gen 2 cable.

With this new cable I only transfer data at 38-42MB/s.

I also got a replacement cable when I complained about the first one, but it also transfers at 38-42MB/s.

Is there something I’m doing wrong here or are the cables just crap? At $40 each for these cables i expect better.

Motherboard im transferring to/from is Z270 ROG Code with current BIOS.

Also get the same speeds transferring to my Galaxy Note 10+ USB 3.1 internal storage. The cable does charge the Note with the 45W PD2 charger super fast charge 2.0.

The cable itself is advertised as:

USB C 3.1 Gen2 SuperSpeed 10Gbps E-Marker chip Fastest Charging USB Cable, Oculus Quest Link Compatible (White, 10 Feet)