First off, let's remind ourselves why she doesn't much care for male superheroes; as she told Hentjes, she wasn't interested in male superheroes because, as she saw things, the men around her were weak and easily handled; therefore, the Greek gods who were all-powerful were unrealistic and thus not worth reading. What the poor dolt never quite saw was that it used to be considered unmanly to threaten little girls; her inability to take that into account because she was too busy being an angry, impatient self-hating idiot to pick up on social norms means that she equates being a decent man with being weak. The same impulse that has her venerate John and Mike for being unrepentant dicks leads her to reject the superheroic.
Another failing of hers is the rather predictable assumption that women who aren't burning with envy of other women or crippled by the irrational, self-defeating belief that they're ugly and fat because abusive jerks who get off on their pain say so are flaunting their good looks in order to torment her and make her feel bad about herself. April's baffling and counter-productive belief that Becky wants to crush her with her star-power because that's what pretty people do comes from the same place in Lynn's psyche as her default hostility to Wonder Woman and all the other female heroes.
This hatred of male authority and jealousy of other women has the result of her being more inclined to read things like Scrooge McDuck and Little Lulu; the problem is that her very real need to not want to pay attention to her surroundings or devote mental energy to figuring things out means that she sees their adventures on a simplistic level that allows her to miss what's really going on. As an example, most of why she laughs at Scrooge McDuck is because talking animals are funny. Since she's too superficial, too inattentive and too lacking in empathy to pick up on why Scrooge has his money bin and why he's so driven, she cannot realize what a messed-up nutbag the old coot is. She sees a cartoon millionaire; we see an angry jerk who can't relax until he's whupped the whole damned universe. Also, it ain't like he lives in a paradise either. Duckburg, as we all know, is jam-packed with greedy, submissive and stupid people filled with the craven eagerness to act like fools while either celebrating one foolish festival after the next or enslaving themselves to some moronic mass psychosis of a fad.
She even fails to notice what's really going on in the world of Little Lulu; she sees a cool kid having cool adventures. I see a rather ordinary child hampered by a hysterical jerk mother covering for sitcom lard-head daddy. Since I remember how spank-happy the tight-assed, status-obsessed vermin parents are, I'm a bit closer to the truth than she is.
To summarize, the reason Lynn doesn't get pop culture is that that would require her to do something she hates even more than apologizing: paying attention to what's going on around her.