Yes, I like this explanation. There are magics that are taught, a precision spell craft, akin to science, some are saying.
Wanda always had energy that she had some/later more control over.
Magicians like Strange conjure the energy for the effects they command or wish.
Witches or other like Wanda have the energy or have more 'inherent' ways to conjure / create it.
I can't put it my 'casting finger' on it, but it seems relevant to distinguish 'folk-type' magic from Strange's conjurations.
A part of me wants to go with the East/West division. Strange's magic is more Eastern, or has that feel or something.
Wanda's seems more old world as in European.
But these are window dressings to some degree. There is ancient folk magic in India or China, for example.
European Ceremonial magick. (Dee and Kelly, Crowley perhaps) are the other side of that.
Probably even more ways to dice and slice the whole thing.