I personally interpret Vallee’s ‘control system’ to be an adaptive mechanism within our individual and collective psyches.
There must have been numerous of these acting during the long course of our development. When you think of how drastically, and relatively quickly, a new technology - even something like writing - can change us and our worlds, it makes sense to me that we might require or evolve an ‘adaptive’ mechanism like that.
With regard to ‘a “flat land” approach to a much more complex phenomenon’, this could very well be true of some experiences. One thing Vallee has written is that the phenomena are showing us that we don’t understand time and space.
You might enjoy Terence McKenna’s take on this—a variation on what you saying:
https://psychedelicsalon.com/podcast-261-the-definitive-ufo-tape/
I just loved this quote:
“information is loose on Planet Three. Some kind of very strange thing is going on.”