MM Lacking Detail?

Has anyone else noticed that Level 3 for MM has been way less detailed and he leaves out a lot of topics?

I used him for 1,2 and never read the book but feel like I’m going to have to dive into the book to replace the gaps here. Anyone have a similar experience?

Cue the “MM is a supplement to the material you need to read the book and shouldn’t rely only on outside material”