I had this mostly written up, so I'm going to say pretty much what my sibling said in a different way :)
It's not about the ruleset so much as the players' attitudes.
There's a way to play Apples to Apples that's as a card game. You deal the cards, flip a topic, everyone puts up, the judge reveals the cards and picks a winner. It's pretty boring unless the cards themselves are hilariously lewd, hence CAH. (And I've played rounds of CAH this way that were just as boring.)
There's another way to play it, more like a role-playing game with the cards as a prop. The judging is a discursive experience played with the whole group. When the cards are revealed, due attention must be given to each one. "Fuzzy like teenagers. Fuzzy like... The Clinton administration? Fuzzy like herding cats, okay. Fuzzy like... Dinosaurs." Once all the cards are on the table, the judging begins. Unlike in the card game version, the cards which aren't relevant must be dealt with explicitly, and audience participation is encouraged.
"Dinosaurs just aren't fuzzy."
"What about pterodactyls?"
"Yeah, birds are technically dinosaurs."
"Okay, but birds aren't fuzzy, they're fluffy."
"Maybe it's fuzzy on the inside. Like dinosaurs have nice personalities."
If I'm hawking my own card, that's minus points. Or is that not my card, and I'm trying to sandbag it with praise? Complex interpersonal dynamics meet linguistics as every judge's turn becomes a little game to itself. And just wait until cards start to turn up that tie into previous rounds...
It requires the players be engaged and committed to playing with each other, rather than with the cards, but it's hopefully obvious how that's fun in a way that has little or nothing to do with the content of the cards themselves. So nothing against CAH or other forks, but people who think CAH is fun where A2A isn't probably don't understand what makes the concept fun in the first place.