I am facing same problem. I have even tried reinstalling Big Sur from MacOS recovery but it doesn't work. I have been using Mac for the last 10 years and have been installing betas but never faced such issues so far. I am stuck now and need a solution asap.

Same issue here. BigSur beta 5 is the worst update so far. I will think twice before installing betas on my main machine MBP Touchbar 2016 henceforth. I have issues with Norton Wifi Privacy ever since i installed Big Sur on my machine, it doesn’t start and it freezes. Even Norton Internet Security is also giving trouble. I have uninstalled both but no luck. Looking for a solution/update so that i am able to restore my macbook without loosing data (without erasing the drive).

Thanks Sqrabs!! Yes, It is the Symantec which is culprit and has been causing system un-stability issue. I followed the steps as below: 1. Reboot into Recovery mode 2. Open the Terminal, execute command, csrutil  disable 3. This will disable system integrity protection 4. Reboot into Safe Mode, 5. Open the Terminal, execute command, systemextensionsctl list 6. This command will produce the information regarding system extensions. 7. After this, In my case I executed command, systemextensionsctl uninstall 9PTGMPNXZ2 com.symantec.mes.systemextension 8. This will take a few seconds to uninstall 9. After this you would need to uninstall all the Norton Apps from your system 10. Finally Download RemoveSymantecMacFiles.zip 11. Unzip and run RemoveSymantecMacFiles.command file 12. Restart into Normal mode After this I have noticed that the issue has been resolved completely. I am able to use my MBP without any difficulty. Please make sure that you do not install Symantec apps again because it may cause system instability issues again.