What is really bizarre to me is that I followed the steps (disable handoff, sign out of iCloud etc) - and still in chrome 88.0 and big sur 11.1 - edit > command+C copy (and paste V) are disabled (greyed out in the drop down from edit) but the shortcuts still work?!?! Nuts. I have also been able to get around this annoying issue by doing a right-click on some parts of selected text to allow copy.