potatotomato
Small text-based programs are nice because they're low-investment to learn, are often well-documented (through man pages), and sometimes composable. I use grep, man, git, rsync, and the basic shell utility progs constantly. I spend all of my time in emacs though, which is pretty much opposite the trad unix philosophy-- I think there's something to be said for a unifying / monolithic interface, even if it's not ideal (I could never get used to window transience).
Unix tools are anything, but low-investment to learn.
Surely the initial investment might seem low, open up the man-page and then figure out which combination of cryptic flags you have to use to do what you want.
But you are actually not LEARNING anything at the time. What you have to do instead is REMEMBER all this useless trivia and all gotchas.
And every time you want to do something you have instant-recall it, or read the same manpage for the Nth time. Unix shells offer little - if any assistance in this - or any other process.
That's if you're lucky and remember which tool it is to begin with. Sometimes I remember that there was a tool X with flags Y which did something what I want to do again now.
Now good luck finding the tool X (remember the unix tool names are "very descriptive") and then figuring out which flags Y you had to use. So easy to learn.
Open up the man page for "tar". Learn it.
Compare it to learning how to work with archive files in Total Commander. Well they work almost exactly like folders do. And that's it. You don't have to relearn anything ever again. The skill sticks. You might forget the hotkey but it's always there in front of you, and you don't really have to read documentation ever. And it works exactly like you'd expect it to.
The fact that you have to read documentation to do the simplest things is insane by itself.
Mind you, the 'man' tool doesn't even have any kind of navigation functionality in it. There are NO LINKS in man-pages. It's a bare-bones text formatter/reader.
It's like the software from 1960/1970ties. And not even the good kind.