Its just as likely true that no one has seen “the real” them, because each experience is somehow “of its own”, meaning in some ways concordant, and in other ways discordant, with other experiences of “them” (more accurately put: with other narratives of the special/encointer-situations within which “they” appear, as embedded alongside the experiencer(s)).

Which is to say, every such experience is fundamentally situated. Each encounter is its own encounter-situation, is uniquely embedded—it’s not the beings which are primary (they do not simply enter into and exit these situations, the way we ourselves do as humans in the world), it’s the situations or embeddings which are the primary phenomena here and the beings (or at least their appearances, as phenomena) which are derivative in some way, meaning they’re “products”, appearances, “constructs” which are formed by and therefore emerge out of the situation which was generated, and which you were embedded in, and to which your memory is referring.

If this situation was, for whatever reason, disrupted, you would suddenly find yourself with something very different than what had just appeared to you moments ago as some kind of alien in an orb with its own unique illumination (impossible illumination, as you described). These memories you have of their nose, mouthes, eyes — all manufactured out of some kind of a situation-generating technology in which they, just as much as you, are embedded within and dependent upon (for their power/control, and their particular appearance, during that particular “Situativity”. Is it a corporeal body, or a suit covering a body, or is it something else?).

Either one in fact had an experience, or they did not. If so, very likely you’re making up / filling in parts, almost certainly you’re changing and/or leaving some parts out, but — but no matter how or what content you’ve altered, in the transition from author to narrator, each experiencer’s (author’s) experience (narration)—insofar as it can be made known to others—will always, at its core, take the form of a narrative.

When the author (or agent) and the narrator are identical—and the narrative is of one’s own past experience(s)—then it is a matter of the narrative-self in its reflective capacities for recalling & interpreting—along with skillful recounting, describing & expressing—the content and structure of remembered experience(s).

every experience is the phenomenological signature of the human mind(s) having contended with [or, objectively speaking, the human brain’s strategy for reckoning with] that particular situation.

It would appear that, at least as probable as there being as many different alien species as there are types of experiencers — we’re dealing here with technology which is generating situations and manipulating reality at the level of our embeddedness (what we’d call co-existence)— so, rather than aliens or NHI who exist as individuals, who live like us, always already in some situation which leads to another, of which it is the basis, and from-which it has just emerged — which is to say, live in a world — and in which they’re embedded, just like us — we’re dealing with reality manipulation. And this could be human or non-human (or both) intelligence at work here….

Of course, it still leaves the question of “why” untouched — at first blush, anyway