WARNING: The following contains spoilers for Boruto: Naruto Next Generations Episode 219, "Return," now streaming on Crunchyroll.
In the classic Naruto series, it was tough to really accept he and Sasuke patched things up due to the show's rushed ending. They fought off Obito, Madara and Kaguya, but Sasuke turned on Naruto right after before realizing they were on the same side. Sasuke eventually became a Ranger while Naruto took steps toward becoming the Hokage, but we didn't see much warmth and brotherly love thereafter. Even in the movies, the bonding moments weren't there as they were wrapped up in duty. However, the Boruto anime has a couple key moments that prove Sasuke really does love Naruto like a brother.
Naruto has never hidden his love for Sasuke, adamant he'd bring him back to the Hidden Leaf with a clean slate after the sulking ninja was corrupted by Orochimaru and the Akatsuki. But Sasuke just isn't that emotional type of guy -- even with Sakura and Sarada, as it's not in the Uchihas' nature.
But after the current war against Isshiki and Kurama's death, the love is spotted in how Sasuke's leg was used as a pillow to cushion Naruto's head. The Hokage was out cold after the battle, with his mind in the astral plane saying goodbye to the Nine Tails Demon Fox, yet Sasuke was taking care of his physical frame.
What's astounding is Sasuke was beaten and drained from the scrap too, especially as he used a lot of chakra via his ocular jutsu. Boruto confirmed he doesn't want his brother and leader to die, putting to bed any doubts of him as he reminds us he's a hero and Naruto's family.
In addition to this bit of detail, when Boruto activates his Karma mark to open a portal back to Konoha, Sasuke still has Naruto's best interests in mind. He helps him up and rushes him through the rift to get back home as he knows Hinata, Himawari, Shikamaru and the others are waiting on their icon. It reinforces that despite all their differences, their brotherhood is clean and pure. In this case, Sasuke just got his Rinnegan eye dug out by Boruto (who was possessed by Momoshiki at the time), but nonetheless, the Hokage is his priority.
This goes beyond the job of Sasuke being a bodyguard and protector; this is him repaying Naruto for years of faith and belief. After all, Naruto stood up for him against the Kage council, making it clear he trusted Sasuke to redeem himself. Not even Kakashi had such belief, which ironically left fans sad the grey-haired shinobi couldn't see Sasuke babysitting Naruto like this.
It's something Kakashi wanted when he trained them in Team 7 as youths, but ultimately, it's just endearing to see it happening on the whole -- even if it's just in front of Boruto and Kawaki. This sentimentality in Boruto actually helps them reassess their bond, wanting to train together to become the next iteration of these two legendary heroes.
