It’s common to see people complain about continuity errors or scientifically inaccurate events in entertainment these days. Is this a modern tendancy? Were people in the past more likely suspend disbelief and just accept something as entertainment?
Sherlock Holmes fan societies have existed since the 1930’s, dedicated to what you might call fanwanking. I think there were science fiction societies forming around the same period.
Hell no, personally I’d argue that theology is largely comprised of nit-picking debates. Consider the difference between homoousian and homoiousian and the trouble that created back in the 4th century.
Sorry, I skipped over the ‘entertainment’ requirement.
How about the Homeric scholars of antiquity - an example:
Sounds like the same kind of thing Comic Book Guy would be into.
Not sure if this counts as it’s non-western, but in Peking Opera “getting it right” is essentially the most important thing. If the performer makes the slightest wrong movement he’s in trouble! It would be a nitpicker’s heaven 
it all started when Star Trek was so poorly written and even worse was the acting.
People these days are far less likely to suspend disbelief than they have been in the past; many are completely resistant to the concept. Part of it is that the Internet allows you to look up things quickly to nitpick immediately.
There’s also a different attitude. 25 years ago, nitpicking was a game. If you found something wrong, you’d point it out, amused, and then continue to enjoy the work. Now, it’s serious and if you find the slightest nitpick (even in some cases where it’s merely your own lack of knowledge), you immediately start complaining about how it “ruined” the work and “took you completely out of it.” Ultimately, it an issue that people just don’t understand that fiction isn’t fact and a way to show off your own supposed superiority.
Now, there were probably some who took it so seriously in the past, but not many. The book Film Flubs, which was the first to collect film errors, was written as an amusing sidelight and mentioned that, sure, these things happen, but making a film is complicated and sometimes they get missed. Now, when someone finds a flub, it’s all “God when I saw that they drove a 1957 Chevy and film was set in 1955, it ruined the entire movie for me.”
There are threads in this forum every few months that are filled with this sort of nonsense.
The Baker Street Irregulars, when faced with inconsistencies in the Holmes mythos, would come up with elaborate explanations to explain it all. With today’s sensibility, the would have condemned Conan Doyle for making them and vowed never to read anything more by him.
It also seems similar to Mark Twain’s “Fenimore Cooper’s Literary Offenses”.