I'm having similar issues - my Macbook keeps restarting randomly! Apple should really fix this immediately! Besides from this, I'm having issues connecting to the Wifi and my personal hotspot randomly - the issues are completely messes up my working life these days. A restart often helps the internet connection issues, but I'm not prepared to have and expensive computer, and then having to go through so much trouble constantly. Also, restarting the computer doesn't work most of the time - it closes down some of the programs and then just stalls in the process letting me know that Preview hindered the restart - though Preview seems fine. In addition, the force quitting function doesn't work when I'm having this issue. Only option is harsh manual button down turn-off the computer. On top of this my computer is struggling bad with a whole lot of ventilation-noise just from having my email, Word and Safari open. Its a 2,3 GHz 8-Core Intel Core i9, Intel UHD Graphics 630 1536 MB from the end of 2019 Talked to the Danish Apple support last week and they reported that there were no general issues with the Big Sur update - should have googled before calling ;) Never experienced so many systematic issues with Mac ever before - hope they fix this ASAP or I'll have to continue my PhD-thesis on a Windows computer