lol, i am in my 40s and i get ASMR. big time. i remember stumbling across a community a long time ago and immediately recognizing the fumbling attempts to describe the sensation, because it's not universal and i had once tried to explain it before as a teenager and failed, embarrassingly. also, some people have certain "triggers" that others don't, or are less reliable. and sometimes the triggers are less about the action and more about the memory connecting to an earlier experience.

in those early days it was about finding/sharing videos online that gave the sensitive viewer the sensation... which is sort of like transfixing or mesmerizing. my first experience that i recall was IRL as a 1st grader when my desk neighbor was explaining a math problem to me that i already understood. just sort of quietly talking while tapping / scratching their pencil lightly. it was like being caught in something, but pleasant. another time IRL i was in a meeting with this guy who was like late 50s and he had this meandering style of speech with a low voice. same deal, i was just kind of there, locked in, and could have listened to him prattle on about literally nothing of consequence for hours. i could snap out of it, but i could feel myself not wanting to, even though the meeting was a huge waste of my time lol. i also remember getting it from watching some public access channel as a kid for a show where they did algebra on a whiteboard for some local community college. and one where they taught conversational french that was recorded in the early 80s, when they would go over conjugation. super-chouette!

the way the phenomenon has exploded i attribute to monetization, because in those early days of people looking for videos they were all these like random clips of unintentional stuff. like a guy demonstrating a suit fitting, or a transferred VHS recorded lecture on body posture. so like some youtube channel for a very niche audience would have like 15-50 views on their dozen or so videos and then one that would have like 3.2 million views lmao. and frankly, if i just search ASMR on youtube, like >95% of the content is way off the mark. like annoying, weird etc. some up close face making mouth sounds.

it's really only probably something like 1% that hits it, and usually it's not content that is made to produce ASMR. this has been recognized broadly by us ASMR enjoyers and there are entire communities that chase and curate collections of "unintentional ASMR", which honestly has a better track record in my experience.

though, there are exceptions: content makers who seem to know they are giving off the whammy and how they are doing it, but they tend to be associated with the "fascination" and "mesmerism" community which is more adjacent to weird hypnotist stuff and those grifts.