Vim is a weird editor and it works.  The default scheme makes it super hard to see comments and there could be important things there. For example commented options for a given service.

Here's a video walkthrough

To change the scheme you need to press ESC key and then

:colo desert

This will allow you see things more clearly.

To set the Vim's color scheme globally and system wide you need to create/update /etc/vim/vimrc.local file and add this line

colorscheme desert

press ESC key and then press ZZ to save and exit

You're all set.