I'm running a clean install of Big Sur on an old Intel Mac Pro.
When I install the latest drivers for my SANLink 10G Base-T, everything seems to go well.
There are no warnings or prompts from my Security panel in Settings, and my 10Gb network immediately appears in the Finder.
But when I restart, it's as if the drivers are not installed. SANLink Utility doesn't see the adapter, and adapter settings are not available in Network Settings.
Thanks for any ideas.