I think these ones are mostly estheticians / beauty therapists who specialise in skin - lots are East Asian patients, lots of the therapists who post the original videos are in Vietnam. And I think there are quite a lot of patients in Vietnam who have extreme blackheads that are in some way related to historic use of Agent Orange (chloracne)
I read that on Reddit, doesn't mean there is any truth to that explanation. But lots of the people who create the original videos (most of the ones on YouTube are actually ripped off and reposted) are beauty therapists, in East Asian countries (though lots have comments or descriptions, I don't know the languages to recognise the characters!)