Wireless adapter unclaimed after update and reboot
In our chat, we learned that the package linux-modules-extra-5.11.0-22-generic that provides the driver iwlwifi among many others, didn't get installed in your upgrade. I suggested that you do, while booted into kernel version 5.8 where the wireless does work:
sudo apt update
sudo apt install linux-modules-extra-5.11.0-22-generic
Upon rebooting into kernel version 5.11, your wireless is now working.
I also recommended:
sudo apt install --reinstall linux-generic
...because its dependencies and their dependencies include linux-modules extra.