Linux

As a terminal fan, my main reasons for preferring them over a gui (for some tasks) are:

1. It's faster to type than to navigate menus
2. If I don't know where something is and can't guess it instantly, it's usually faster to search for it in a man page than randomly digging through gui menus
3. You can combine commands with each other with pipes or $()
4. You can search through your command history to find previous commands
5. You can write scripts and aliases to automate common tasks
6. The terminal requires less context switching. Typing ten commands is less mentally taxing than opening ten different guis

The barrier for entry is higher with terminals but unless you need visual feedback (e.g. because you're editing an image) it's easier and faster for both common and rare tasks.

It's way easier to communicate a terminal based solution over the internet. Instead of making a guide with images, possibly needing annotation, you can just say "run x, y, z in order" and the user can just copy and paste it (even though it's a bad habit to run random commands off the internet)

I just find certain things to be quicker in the terminal than doing it through a GUI.

Like installing software. I think it’s quicker and more direct to do something like sudo pacman -S Firefox than to go through a gui. Especially if Im using a drop down terminal that I have hot keyed.

As for remembering everything, I’d say it’s just a matter of experience. Like, you had to learn how to use a GUI app at one point or another.

This is what sucks about Linux. It’s still not as complete as Windows in that regard… Things being too techy, even the real user friendly ones still got it.