Downloading windows support software from bootcamp assistant deletes windows efi bug?

hello,

i wanted to do a simple WindowsSupport download on bootcamp assistant and to install updated drivers on my existing bootcamp.

i selected downloads folder as the destination.

on finishing download, it starts spewing out thousands of repeating message about not enough privilege, and it will not close.

i reboot my macbook, and bootcamp entry is missing from the bootloader.

i checked the efi partition and all microsoft windows efi files were gone.

i was able to restore them by using bcdtool on windows install media. fortunately, bootcamp partition was unaffected. phew.

what gives? is this a bug?

i am using mac os catalina on macbook pro early 15