You raise an awesome and very important point here that I think is relevant to the vast majority of us here on the forum. The eDNA content does SUCH a good job on DAX training, that for almost all of us that’s our comfort zone.
However, @nick_m and @melissa have both said something to the effect of (and I’m grossly oversimplifying here) “if something can be done upfront in Power Query, it probably should be”. This was a huge revelation to me, but as I’ve tried to implement it more and more over the past few months rather than just jumping right into DAX, I’ve come to realize that in many/most cases, it is the best approach both from a performance standpoint and also in terms of making your DAX much simpler and easier for others to understand.
Toward that end, I can’t recommend @melissa’s Enterprise DNA TV YouTube Videos highly enough. By working through these in detail (often multiple views per video) and forcing myself in my own work not to jump immediately into back DAX when I struggle with PQ, I’ve started to gain a much more balanced skill set that has been enormously beneficial. It’s hard work at times, but also really rewarding because, while totally different in structure and operation from DAX, M code is incredibly interesting and powerful in its own right.
So, you are spot on in thinking about DAX as just one force among many.