I rode the Ember train from 1.4 to now and it was an extremely ehausting process to get to 2.0 with nearly every version requiring frustrating architectural rewrites. The upgrade from 2.0 to 2.8 took like 15 minutes and didn't require a single major refactor. I'm not trying to switch context away from a discussion of Rust, that's just for example purposes of stabilizing.
I found myself struggling to find guides that still worked as written and I was looking at guides because I failed to become competent from the Rust book and Rust by example alone so I wasn't able to diagnose the upgrade path for the content. This has stopped my learning dead in its tracks every time.
To be clear, I have no CS background or functional programming experience so I'm not the target audience and I don't mean any this as a slight against the language.