Disclaimer: I don't own Naruto.
One of Naruto's first acts as Hokage is to strike off Team Seven from the roster, permanently. There will never be another Team Seven; Naruto has seen to that.
He doesn't think that the name itself is cursed. Naruto's not like Tsunade; he doesn't believe that an object or a name or even a person can be cursed. He doesn't fall back on superstition to hide his own failings, or at least he tries not to. But somehow…
Team Seven seemed ill-wished from the start. Kakashi was indifferent, Sasuke was dead in almost every way that mattered, Sakura was useless and Naruto was hollow thanks to his pain. As long as they were together, they did nothing but wound each other. Where other teams bonded, they held each other at arm's length.
For a while it was all perfect in the way of dystopia and disunion, and then everything just shattered, the epicenter of a broken mirror stretching outwards and gaining more shards by the second.
Sasuke shattered the team, but it was Sakura who first put down fractures, Naruto who widened them, and Kakashi who failed to heal the rift as he should have. It's unfair to assign blame to just one; they were all at fault. Rivalry grew, on the surface over the nature of strength, and subconsciously over a girl (the worst and most poisonous type of rivalry), and Team Seven writhed and screamed like the snake cast in the fire.
After they split, the four began to grow and flourish on their own as they never could have when confined by Team Seven, even when their paths sometimes took dangerous and immoral turns. The lived and breathed on the free air, while the invisible cage of Team Seven became a seemingly distant nightmare.
It was when a smaller Team Seven was reassembled, cramped back into a uncomfortably confined space with all their failings and the realization that some things never changed, and when they were pitted against their missing wheel again, that the walls started closing in.
Old wounds started opening on their scar lines.
Kakashi watched as the world screamed and his students burned.
Sakura saw the truth of Sasuke's dark heart and Naruto's feelings for her, and ran away.
Sasuke withered.
And Naruto bled.
The room kept getting smaller and smaller, the confrontations more lethal with each time, as the options that they once had went up in smoke and morals and principles were sacrificed like lambs before an altar. Sasuke and Naruto circled closer and closer, each edging closer to Armageddon, and then everything just…stopped. And then exploded.
The aftershock was nothing compared to the initial strike, but it was the aftermath of the firestorm that consumed Team Seven.
Kakashi is broken by his steadfast failures, broken watching something that he should have nurtured under his wing turn upon itself and violently perish.
Sakura is growing more like Tsunade (and ruing the day she first started to say she was like her master) everyday, an underage alcoholic consumed by her own grief, and, like Tsunade, selfish enough to disdain and discount the grief of others as being petty and unimportant.
Sasuke is dead, in every way that matters. There is nothing else to say.
And Naruto is hollow, his life subsumed by the kage's hat and every "should-have-been".
Kakashi could have told Naruto a tale of another Team Seven. But it wouldn't have helped. The other Team Seven was another team of "should-have-been's", a team that just never mashed, no matter how hard they tried.
So Naruto erases Team Seven from existence; there will never be another one, and there were never any true ones to begin with.
There will never be another Team Seven, because Naruto is not cruel enough to sentence three more genin to the fate he and his teammates suffered.