Something else I just thought of. 2 days before I updated Windows I switched internet provider from Roadrunner to Spectrum. I don't know if that plays a part or not. I didn't check the error log until after the Windows updates.
Do you have any automatic backup software running? I ran into this with a WD external drive and their Smartware program. It runs silently in the background and slows shutdown until it finishes the file it's coping.
Software compatibility is one reason business is so slow to move to a new OS. Many have exotic software that doesn't get updated to new a OS. That was also a factor in business hanging on to XP for so long.