My monitor claims to have 3x USB 3.0 ports, but why don’t they work correctly when the monitor is connected via USB-C?

I recently purchased a HP Z27 monitor. It’s 4K/UHD, and supports video input via usb-c. It also has 3 “downstream USB 3.0” ports that are available for use when the usb-c cable is connected. I’m connecting it to a Lenovo X1 Carbon (7th Gen), running debian testing/bullseye. It has 2 USB-A ports, both labeled with:…

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