Also, the fact that most common use-cases are very common makes using the command line very google-able. Oh, you need to create thumbnails from a folder of 10000 video files, then rotate, crop, rename and archive them? Guess what, you are not the first.
This is the best part about it for me. It’s like finding the perfect code snippet or example for what you’re trying to do, but for all kinds of stuff on your computer and not just inside whatever project you’re working on.
I’m not any kind of command line guru, but the terminal is the first thing I open any time I fire up one of my VMs.
This is really the only answer. You will always be afraid to use something you are unfamiliar with or don't trust. Command line is very useful and quick once you learn it.
This. I used to also keep a notebook with me and jot down the commands I used often. Eventually I learned other ways to jolt my memory and learned to use man. As time went by I used my notebook less and less.