My understanding is that Kemetic reconstruction is one of the second wave of reconstructionist religions that originated in the more general pagan community - an outgrowth of people wanting ways of relating to those gods they considered more "authentic", inspired by the example of Asatru and similar religious revivals. If my understanding is correct, then, it could in part be rooted in a conscious rejection of modern-esoteric Egyptiana - whether ceremonial magic, Isian witchcraft, or whatever else - as insufficiently authentic.
<nod> That was the lens I was seeing the original question through - history-of-the-neoPagan-movement geek that I am, and with possibly-related convos w/r/t Celtic paths fresh in my mind (when I mentioned other cultural paganisms having a similar divide between the Romantic and scholarly-historic conceptions, Egyptiana was what I particularly had in mind).
Sunflower