Btw, I would recommend this (learning a new keyboard layout) as a refreshing exercise for anyone who has forgotten what the learning process feels like. I imagine trying to read a book in another language is similar.
This is especially interesting to me. I've been relearning how to type on an Alphagrip and for much of the process (20-50wpm) I have felt like it was dumbing me down because my thoughts all have to wait for me to slowly output them. Now that I'm past 50wpm on alpha text the effect isn't as bad, but I still feel hindered. (But.... that's worth it for not exacerbating carpal tunnel issues, right?)
With "Let's Plays", you're there for the commentary, it's not just a quiet walkthrough. The downside of this is that you, as a viewer, have no timely input (episodes are sometimes done in batches and uploaded over a week or two). But.. maybe that's the attraction, back to the days of yore when you would yell at the Jeopardy/Wheel of Fortune contestants for not getting the obvious answer!
Source: I watch LPs constantly while working, it's good background noise and gives me an easy outlet to divert my attention.
Honestly, how is GitHub anti-educational once you get past the fact that several students set up a Gitlab server and learned from it. That's a one time benefit.