Wouldn’t it be sad if there was some horrible disaster and that was the main source left of how life was like at this period in history?

But anyways, would you happen to know anything about actual numbers of active numbers of "church’’ members, because I heard it was similar to other cults and counts anyone still living that was at one point or another a member in the total membership number.
The answer to that question depends on how you define “Scientologist.”
The Church’s definition is anyone who’s ever taken a course. By their definition,
I’m a Scientologist, even though I do not now not have I ever considered myself one.
We could use the membership numbers of IAS, if we knew them, but I think that’s probably not workable either. IAS membership would include a
lot of lifetime members who are no longer active. Regardless, you would be looking at, perhaps, 100 - 150 thousand globally by that count.
Most critics of Scientology point to what little scientific data exist on the subject of people who self-identify as Scientologists. That number, the last time anybody did a study, is about 50,000 in the United States with, at most, about 20,000 in addition to that globally. The US, and a few other countries, do track self-identified Scientology figures in the census. Their number generally agree with the academic research on the subject. That’s problematic, however, because a great number of self-identified Scientologists have either formally left the church or have simply “dropped off the lines” in recent years.
I think a better number would be the number of people who received training or processing, other than the Introductory Services, at any Scientology Org in the last year. By that reckoning you have
maybe 30,000 Scientologists world wide. Sure, they have lots of buildings and the look very nice, but try walking into one of them sometime, there’s
nobody there. They have trouble getting even a few hundred warm bodies to fill a small auditorium in
Los Angeles for goodness sake and that’s with mandating that all contracted staff (SeaOrg or otherwise) in the entire state of California show up.
What few internal stats are available tell a similar story. Sales of Dianetics are way down, and that’s with the new “Golden Age of Tech” edition that every Scientologist is supposed to buy. Stats on Clear and OT level completions at Flag in Clearwater are way down as well. We’re talking perhaps a few dozen OT completions (any level) annually at what is purported to be the biggest and best Scientology Org in the world.
Long and short, there never really were that many Scientologists and they are rapidly imploding.