Mostly yes, but they're in general oversimplified (for obvious reasons)

But it's more about offensive cyber security than necessarily the Linux part. The Linux part is just file system navigation and not much more, the rest is the "hacking" part, and that's what I'm talking about

Disclaimer: I did not complete it, but I got pretty far, and I worked in the cyber security area.

I would however say it's not a good place if you want to learn as that's not really the game's focus. There are better resources out there like overthewire and linuxjourney for that