Excellent summary. The adventure is clearly written with D&D in mind and would be harder to adapt to other systems, although it's certainly possible.
That there are some systems that do not have a Perception style mechanism does not mean that the adventure is "DND-centric", that just means you're running a system that probably doesn't act as a simple translation target for the adventure.
With a little effort, you could work this into a Cyberpunk campaign, as Night City is set in the United States after all. Or you could just create a more story appropriate version of Hubble in the world of your choice.
I read through the campaign, and it seems fun enough if done right.
The real world and fantasy world interacting is a trope that has existed for centuries.
A friend of mine played a D&D game where the party got sent to real world Earth. None of their magic worked. After they killed the first cop that stopped them, the half-orc barbarian promptly accident shot himself and died while examining the dead cop’s gun.
My friend said the adventure was hilarious.
There's not much difference to a common denizen of a fantasy world between a wand that shoots bolts of lightning and polished chrome laser pistol tube, or between a flying carpet and hover car. It's all the same to them, and the whole "our ancestral civilizations were so knowledgeable in the lost occult arts that they could shape magic into common objects" when it's really just forgotten high tech sciences is always a fun bit of world building.
This kind of material absolutely belongs in fantasy and I really hope that someday sci-fantasy makes a big comeback, some of my favorite reading books and inspiration for tabletop material have come out of them.
Hard to be a God was a good read I enjoyed and feels like it falls into this category as well, from the point of the "higher beings."
A lot of famous early pulp fantasy didn't make as much of a concrete distinction between science fiction and fantasy either and tended to blend the two freely. I think most people would think of Conan as pure fantasy but there were a handful of stories about him encountering otherworldly alien beings and sci-fi technology, or ancient highly advanced civilizations whose progress is incomprehensible to (in Conan's world) modern inhabitants. IIRC there was at least one Fahfrd and the Grey Mouser story where they come across an interdimensional traveler.
If other people have recommendations too I'd love for them to chime in. It's a genre I feel is definitely underrepresented.
Michael Moorcock is another writer who often mixed fantasy and SF. His Dancers at the End of Time series is brilliant and hilarious. Or more straight-faced and pulpy, the Hawkwind and Elric stories are great.
And Jack Vance, of course. As well as The Dying Earth, he did a bunch of comedy-oriented stories in the same setting, starring Cugel the Clever and Rhialto the Marvellous.