My thoughts exactly. Furthermore, this would be great training/practice for eg. Linux Foundation certifications with just the questions and "here's a terminal, go solve it".

it reminds me of the early LEGO robotics programming setup - and how NQC (not quite c) was much easier to use for those with familiarity with programming.

Part of the problem is there are hundreds of ways to use unix tools to get the correct response, so you'd need an entire shell and output parsing to prevent frustration.

I figured that was just a convenient way to avoid all the security problems that come with exposing a shell online whilst also limiting the inputs, although I'm sure there's other ways to do that. Might be nice to have the option I guess.

It's something I would give my interns to learn how to use the command line and how it's supposed to work.

I've found some very good interactive tutorial for Git and such, and it works very well for teaching/learning.