I once had to manage a large, locked-down installation of extremely custom Linux distros running on extremely custom legacy hardware.
Python was not available, and definitely not Ruby, so that eliminates a bunch of CM tools. Not sure if it'd even fit on the ROMs of some of them. The hardware was a mix of ancient MIPS and PowerPC and ARM and x86 in the same stack, so compiling anything for the targets would have been painful. Nevermind kernel/libc versions so old that lots of commonly available tools wouldn't even compile on them. Golang has a minimum kernel version, you know. :P
Guess what all these systems could run though. Good old sh and sshd. I could send/receive files with cat and tar. I could collect system info from /proc. I could do pretty much whatever I needed. I ended up writing a tool very similar to this one in spirit, though not nearly as polished, and I didn't get to take it with me when I left the company.
Shell syntax can be obscure and confusing, but when you have nothing else, a shell gets the job done. I'm happy to see someone had a similar problem and solved it, and then made it a thing. :)