I am running Ubuntu 20.04.1 LTS.  I have my webcam operational here:

$ v4l2-ctl –list-devices

Logitech BRIO (usb-0000:08:00.0-2):

    /dev/video0

    /dev/video1

    /dev/video2

    /dev/video3

Under my Windows 10 guest, this webcam is not visible at all.  Some of my other USB devices are.  I have the guest’s settings set to support USB 3.1.  The cam is plugged into a USB3 socket.

I use the cam for Zoom.  Is there something I may be missing?  With Windows 10 as a host, the cam was visible and usable without issue.  I copied the same guest configuration that I originally used under Windows 10.