Religious weirdness in fandom
Every time I've brought up, in a public meta-discussion, that "this aspect that's being discussed has great religious meaning to me," it's been either ignored or mocked.
I don't expect people to know my religion (Satanic Discordian Feri Witch) nor understand it on hearing the name. But I expect--or used to expect--that when I said, "This means something in my religion; my connection to this topic is a spiritual connection," that would be accepted with the same attitude that meets statements like "Well, I don't read infidelity fic because it's against my religion" or "as a good Christian, I just can't condone incestfic" or "as a Catholic, I find that story disturbing; I don't like the way the author tried to imply that celibacy is nothing but a sham except when the priest is impotent."
And it was a bit of a shock finding out that wasn't true. That Christian and similar-to-Christian religions got a handwaving acceptance, and any level of agnosticism or atheism is acceptable, but other forms of spirituality are suspect... and mention them as directly connecting to one's fannish identity, and be shunned.
And that ties, indirectly, to the point you mentioned: there's a dismissal of those who won't explain What Why How etc about their fannish beliefs/attitudes. There is an unspoken claim that meta-analytical techniques can encompass and understand any idea, that the entire human condition can be filtered through it... and anyone who refuses or fails to do so, is either being selfish and refusing to participate in the community, or is just too stupid to belong here, in our rarified intellectual fannish strata.
There is no acceptance that:
Some people don't want to analyze the reasons they enjoy it--they just want to share that they do, find others who do, and enjoy stuff together*
Some people's way of understanding & describing their fannish interests doesn't fall neatly into aca-vocab, and the communication gap is to much to bother with
Some can do the full academic discussion style, and enjoy it--but not online through shared text; they want facial expressions and posture and hand waving to go with it
Some have an "artistic" approach to fandom--"I show my appreciation for the show through cosplay and making buttons of photoshopped pictures of the guys kissing" and discussion just leaves them cold
and so on.
If anything, acafen might be a little more likely to consider Mary Sue as a phenomenon worthy of serious analysis if not a certain respect, whereas a non-aca fan might be more likely to engage in kneejerk mockery and/or sporkage.
Mary Sue "phenomenon": yes. Specific Mary Sue Fic: no. The anti-sporkage comments I've seen have mostly come across as "oh, don't pick on those poor pathetic people who can't write any better than that; they won't improve if they're discouraged." It's certainly not, "my, what a rich landscape of MarySuefic this fandom has! Maybe that's really a great way to enjoy this canon!"
* This is generally described as a "lesser" form of enjoyment, lacking an intellectual aspect. I take it as "do you prefer your coffee black or with cream?" I don't think one is "better," nor is black "more pure," nor creamy "more fulfilling."