I’ve been using command lines for over 25 years now and the thing that rubs me the wrong way about them is that nobody can agree on conventions with regard to how a CLI utility should work, which limits the amount of knowledge that’s transferable between them. Each effectively has to be learned individually which gets old fast.
I mean I think there's about as much convention and overlap as there seems to be for GUIs at least, and with much more discoverable clarification to boot