I don't have anything interesting to say about how the backrooms phenomenon has evolved in recent years, but I do find it mildly amusing that I have a very different, but equally horror-themed, reaction to seeing "players" poking around in the original backrooms. Because it immediately gives me flashbacks to the feeling that players have found spots where collusion detection has had a nasty issue (because of bad geometry, or floating point precision errors in the physics system or a NaN, or players abusing the physic system to climb to areas they weren't supposed to), and now there's some awful-to-track-down bug to be fixed during a death march crunch time... all of which actually was a somewhat common occurrence during development at the time, of course.
Obviously, that makes me a lousy target audience for this art movement. But it's been vaguely fascinating watching people enchant, essentially, spaces that were experienced, from our side, as an very brittle (but useful!) optimization hack that we were all too aware could be easily broken.