As an aside, if people find this thread, here is the alternative I found for a third person controller which works very well, and is still pretty straightforward in implementation.
It is based on the tutorial by Philip Herlitz:
(huge thanks to him for also making a really thorough video).
If, like me, you want to do a free look camera for your character and not one that just sticks behind, you can ignore the camera FSM and just use a cinemachine freelook.
Then, in the movement FSM, you can replace the two Get Axis actions by a Player Input Get Move vector (although yes, it does require you use the more recent input system). Set the relative to your camera. (As an aside, it also means you'll be able to store magnitude like this and use it for your animator floats !)
Keep the set vector 3 XYZ but only look for the Y/gravity, since your get move vector will take care of the rest.
And lastly, controller move, you can set it to world and not self if you're using a freelook. Add a little smooth look at direction and you should be good !