While the OP title is a gross generalization, it’s sufficiently truthful for the purpose of this OP.
Humans have always fiercely guarded their borders/frontiers … material and psychic.
Largely Western peoples have created and marketed worldwide the technologies and products … especially in travel and communications … that have increasingly facilitated the infiltration of their borders/frontiers … both material and psychic … by aliens.
Poetic justice? … irony? … law of unintentional consequences?
Why does a reply have to qualify as an “argument”?
Why is it not an answer … you asked … “What is your overall point with this thread? What kind of analytical final conclusion are you trying to make?”
I answered … telling people what to ‘see’ is naked arrogance … I try to be humble.
The OP provides a general “direction” … a hypothetical version of human reality … followed by several questions … so far only Mag has more or less agreed with the proposition though she has not addressed the questions.
My assumption is readers can’t … or don’t want to … ‘see’ the proposition.
My ability to articulate my thoughts crisply and clearly is often sadly lacking. While I ‘see’ my thoughts … expressed as black marks on a screen … quite clearly ,I have some empathy for those who want clarification of a particular word or term or ??? and so on. Empathy for a request for a blanket restatement of my thoughts … not so much.