I always read these for the catharsis, honestly. The 'lemon' part is a vehicle, a supercharged situation that strips away all the polite veneer. In canon, their communication is just layers of trauma and misdirected anger. Throw them into an intimate, physically vulnerable scenario in a fic, and all those unspoken things have to come out. It's rarely just passion; it's Sasuke's hands being hesitant because he's scared of his own power, or Naruto crying from overwhelm—not sadness, but finally feeling seen in a way battle never allowed.
You see authors use the physicality to externalize the internal. Sasuke's cursed mark might flare not with anger, but with possessive fear. Naruto's healing factor could manifest as a metaphor for emotional resilience, literally closing wounds as they talk. The best ones I've found use the explicit content to hit emotional beats that the shonen format would never touch, like the quiet exhaustion after conflict, or how touch can be a language when words have failed them for years.
Sometimes it misses the mark and feels gratuitous, but when it works, it feels like a raw, necessary extension of their story. I stumbled on one years ago where the entire scene was just them trying to figure out how to be gentle with each other, and it wrecked me more than any epic fight ever did.