

It can, but it requires creating your own signing key, registering it with secure boot, and signing your nvidia driver.
There’s a guide here: https://askubuntu.com/a/1049479
But if you’re running any out of tree drivers (e.g. the nvidia driver), I’d recommend just leaving secure boot off.
The symbol they defined out is not the equals symbol but rather U+2550, so the for loop is fine.