For anyone who was looking for some of the original courses and your searches aren’t turning up anything, a lot of the onboarding tutorials have been all collected into this page.
Unreal Engine Essentials for Games | Onboarding Collection
It’s not very obvious how to access this and I spent quite a while searching for the actual course names. Obviously not going to solve any of the other missing pieces of the Learning platform, but this is a bare minimum. I do miss the tests and such, but at least the content is still accessible.