It's a phrase, and everyone understands what it means. Wikipedia isn't the worst here, even though it mangles the grammar:

    In summary that has authenticity emanates from an authority. 

(https://en.wikipedia.org/wiki/Official#Adjective)

The only problem here is people pretending not to know that language involves ambiguities, figures of speech, and so on.

To expand: in this case, two things are happening simultaneously: first, the author appreciates literature, and is genuinely happy that their intuitive belief that it is something "good" is getting a bit of empirical evidence.

Second, yes, I believe there is a hint of a smirk in the statement, that, if I were to dramatize it, is a comeback at all the STEM students in college that were dismissive of the author's enjoyment of non-non-fiction. It's all in good fun, however, because the article fundamentally rests on a believe in the scientific method, just not to the exclusion of other human endeavors.

I've met plenty of people who say "I only read non-fiction" always as if it's a virtue. A friend's father told her she made up lies about people who didn't exist. That was his opinion of her fiction. I think some people are really threatened by fiction, and it's unfathomable to me. Perhaps they're threatened because they've been told to like something that's not for them. It can be difficult to not like something when it's implied that not liking it is your own flaw. I feel these people live in a poorer world for closing that out of their lives.

Not being interested in fiction is about as damaging as not being interested in sports. In other words, not at all. Phrasing it as being in a "poorer world" is just normative bullshit, implying that one group is superior and the other inferior based on a point system I never agreed to.

I'm genuinely sorry if I offended you with my feelings. I tried not to, but clearly I didn't succeed. And in a context where everything seems to be treated as a value judgement, I should've been clearer.

There was nothing normative intended, and that's why I used the word feel. For brevity, I left off the bit where I regard my infinite ignorance (including sports, biology, math, religion, and fiction) as my own limitation, and one which I acknowledge limits my experience and interaction with people who cares and know more. Like my dislike of seafood. I don't blame the fish.

Since you identify specifically, let me be clear: Not less, just missing out on something I enjoy and learn from. My own ignorance and indifference limits my world, even if it is a necessary limitation I choose.

I'm sorry you feel judged. Snobbery is truly toxic, and my intent is inclusive. I apologize if my words are not.

https://xkcd.com/1053/

It is very clearly meant in jest. The rest of the article is about breaking down why "according to science" isn't a particularly meaningful term in this case, and by the time the author has reached the conclusion, they are using more rigorous phrasing.