Yes, I installed all of the cable drivers when installing Vivado.
Nothing appears in the Device Manager when I connect the Cmod s7, neither as a COM port nor as a USB controller entry. I tried connecting a USB-to-serial adapter I had to the same USB port, and it appeared right away as COM3. So the port and the cable are ok.
I tried the Xilinx note 59128, but I can't get the batch file to execute under Powershell. I ran PS as admin, and executed the following:
.\install_drivers_wrapper.bat C:\Xilinx\Vivado\2021.1\data\xicom\cable_drivers\nt64 C:\Xilinx\Vivado\2021.1\install.log