We agree that all precautions are little. But I find it frankly excessive to put a cover the camera from your computer. Sliding plastic lids have become fashionable that open and close at will.
I never would. First because it is very, very difficult for someone to hack into your Mac and capture images remotely without your permission. And second, if that happens, I have nothing to hide. I don't usually walk around the office naked. Apple recommends not using them.
Apple has posted a few days ago on its website a support document warning users not to close their covers MacBook with a plastic cover over the camera.
Placing a cover, sticker or tape over the built-in camera of computers is a practice adopted by some privacy and security conscious individuals to protect against unwanted captures via webcam. Now, however, Apple is explicitly advising do not use said caps.
With a document User Help published in early July, Apple urges users not to close their MacBook Pro or MacBook Air covers if there is a camera cover installed on it.
“If you close your Mac notebook with the camera cover installed, you may damage the screen because the distance between the screen and the keyboard is designed to tolerances very small, "says Apple.
The support document also describes some of the camera's privacy and security features, including the green indicator light that lets users know when the camera is active and the camera permission settings entered in macOS Mojave.
If users insist on being able to cover the camera on their MacBook, Apple advises using a cover no thicker than a paper. Obviously, it is recommended not to use a sticker that may leave glue residue when it is removed to use the camera.