I'm going through the phoenix part now. It is very good, but very slow paced at times. Personally, I would prefer if the author focused more on teaching the content rather than spending time on the content being difficult (or not).
I still rate it favorably, though. Good content thus far. I already have some background in Elixir+Phoenix from the respective books. It's nice to learn from relatively well structured videos.
I hope the author makes an advanced Phoenix video course.
OTP, mnesia, macros, umbrella app structure, maybe even best practices with server side templating (eex) + react + phoenix json api backend.