Hello,
I tried a previous version and the WIFI worked (not the sound) when I had Big Sur installed on a partition with Catalina. I have removed the partition, reinstalled BS and now I only have BS. I tried "BigSur prelinkedkernel fix4" and the WIFI did not work for me ... Interestingly (and perhaps it is somewhat circumstantial) I installed the developer version of Safari from the Apple page:
Safari is the best way to see the sites on iPhone, iPad, and Mac. Safari Technology Preview gives you an early look at upcoming web technologies in macOS and iOS.
developer.apple.com
And Tachan !!! I have WIFI working (not sound). It does not connect to Hidden Networks. I have to make my network visible and it can connect without problems. I hope it is not intermittent and that the WIFI continues to work because sometimes it takes a while to activate. I have detected that in BS the search in Spotlight sometimes does not work and sometimes it does ...
I work with a MacBook Pro 13 mid 2012
Thank you very much for the great work you are doing