We are seeing Netskope fails to start after Big Sur update on M1 machines, this kills the network connection. When we log in as 2nd user we are able to get a network connection however Netskope fails to start and requires Rosette to be installed "again". We are 99% sure that Rosetta is installed. : )
I have seen this in my testing on a MacBook Air M1 and now waiting on Netskope support to get back to me on this issue. I was only macOS Big Sur 11.4 and updated to 11.6 then ended up in the same situation you are describing. I was able to remediate the issue by disabling Netskope from the network interface, reinstalling Rosetta 2 and rebooting the computer.