Title says all.
To me, it would be plausible, since we haven’t seen the pilot of the Europan Pyramid
When Ghost speaks to us when “the darkness” is speaking to us, it uses first person
Granted, the idea of the Witness is new, but they could retconn that to being the pilot talking to us
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From my perspective, "Clarity Control" and the other statues are direct icons to the Darkness' power. (which at this point has been proven to be less of an "evil" force and more of just a "force") This differs from the Witness, who is a being who "serves" the Darkness, but through his own interpretation of The Final Shape. Think of how a Wizard (from D&D) would cast wind magic. Wind exists naturally in the world and doesn't need to be directed, but it is a force that can be directed and channeled to produce a desired result. It also has no morality of it's own, but it's use (for good or evil) aligns to the ethos of it's user.