WARNING: The following contains spoilers for Boruto: Naruto Next Generations, now streaming on Crunchyroll.
Recently in Boruto, everyone's favorite No. 1 Hyperactive, Knucklehead Ninja ninja has been going through the wringer. After experiencing multiple overwhelming defeats in a row against Jigen and then a reincarnated Isshiki Otsutsuki, things were already looking bad for the Seventh Hokage. The biggest loss, however, was that of Kurama, who sacrificed himself to give Naruto the power to finally end the threat of Isshiki for good.
While he experienced his fair share of losses in Naruto, this is the first time the character has been made so powerless. While he does have his own massive reserves of chakra, they are nothing compared to Kurama's. This puts Naruto in a very dangerous position, as he is well-known worldwide as the Seventh Hokage and the world's strongest shinobi, as well as the one who killed Isshiki.
With Code inheriting Isshiki's will and somehow being stronger than his late master, Naruto is in a much more precarious position than ever before. Although he is of no real use to Code or the rest of Kara without Kurama, Naruto is still a high-priority target for killing their late leader. Considering just how much it took to beat Isshiki and how Naruto has no real way of doing it a second time, it's clear to see why many fans fear that the Hokage's days are numbered.
With that being said, Naruto has actually avoided his death already during the recent battle. Jinchurikis, those who have Tailed Beasts within them, are supposed to die once/if the beast is extracted from them. This is how he actually "died" back in Naruto Shippuden. However, because of the unique way Baryon Mode works, not only is Kurama the only one that died, but he does so in a way that doesn't kill Naruto, thereby saving his life in multiple ways during the battle.
Another point to take into consideration is the future scene at the very beginning of Boruto. In this scene, an older Boruto and Kawaki are in the middle of a fight with each other -- one that seemingly destroyed the Hidden Leaf. At one point, Kawaki states, "I'll send you where I sent the Seventh Hokage, Boruto," implying that in this future, Naruto isn't dead, but just somewhere else.
While this can be interpreted that Kawaki was being confusingly vague and ambiguous about sending Naruto to the afterlife, there's too much evidence that goes against that theory. Kawaki loves Naruto as the father he always wished he had, and he's made it clear on multiple occasions that he has no desire to see Naruto hurt or dead. Indeed, he's risked his life numerous times to save Naruto, so as it stands, it's a little hard to imagine that Kawaki would kill him.
Another factor to consider is that Naruto is still quite strong even without Kurama. With his large chakra reserves, chakra from the other Tailed Beasts and his Six Paths Sage Mode, Naruto is still easily classified as one of the strongest shinobi in the world, albeit not quite as strong as before. While it's unlikely he'll be able to take on Otsutsuki-level threats like before, he can still do quite a bit to protect the Hidden Leaf Village from them.
All in all, there is much more evidence to support Naruto remaining alive. With still more than a considerable amount of strength for a shinobi, as well as someone as strong as Kawaki dedicating himself to protecting Naruto, he is relatively safe from death. The only major threat to him that's currently known is Code, but with Kawaki and Boruto gaining control and mastery of their respective abilities, Naruto has far less to be worried about.
Kurama's death hit fans almost as hard as it did Naruto, so it's understandable that viewers were worried. With Kurama even implying that Baryon Mode would kill Naruto or both of them at the time, audiences were likely prepared for the worst. Thankfully, Kurama was a sneaky fox and lied. His sacrifice was so that Naruto could carry on living, and it doesn't seem like that will change anytime soon.
