The Amazing Spider-Man was one of Spider-Man: No Way Home's most healing moments, but it was even better when he used his belt.
One of the most emotional moments in No Way Home was from Spider-Man: when Andrew Garfield's Spider-Man rescued MJ from the MCU. In both the comics and movies, one of Spider-Man's most tragic losses was the death of his then-girlfriend Gwen Stacy, who was murdered by the Green Goblin. Similarly, they both saw Spider-Man get a chance to save MJ from a similar fate, demonstrating how occupied Gwen's death was and that he would never allow a loved one to die the same way. However, in the original comics, Spider-Man's reaction is more perfect.
Norman Osborne, aka Green Goblin, is Spider-Man's greatest enemy and one of the most dangerous supervillains in the Marvel Comics universe, due to his unbridled cruelty and brilliant tactical mind. Green Goblin has tormented Spider-Man all his life, but his most notorious brutal act was the murder of Gwen Stacy. After the Green Goblin knocks Gwen off the bridge, Spider-Man tries to prevent her fall with a web, but the sudden stop breaks her neck, leaving Spider-Man devastated and lovable.
In the twelfth issue of Marvel Knights: Spider-Man, by Mark Millar and Terry Dodson, Green Goblin repeats this horrific situation, kidnapping Mary Jane Watson-Parker and taking her to a bridge to once again torture his enemy. When Mary Jane inevitably falls, Spider-Man's inner dialogue reveals that he has been obsessed with Gwen Stacy's death for years, contemplating how to save her and using a different method to prevent Mary Jane's fall, saving her life. While No Way Home sees Garfield's Spider-Man physically arrive and capture MJ, providing a catalytic reparation for his past failure, Marvel Knights: Spider-Man goes even further by putting Peter in the same position as Gwen - depending on his networks to save today.
In the Marvel Comics universe, Spider-Man has launched a series of web lines in Mary Jane, targeting her key joints to spread impact. Spider-Man fired six webs at Mary Jane, one for each limb, one for her torso, and one for her head, ensuring an equal amount of support for her body as it kept her from falling through midair. Even MJ is more amenable to this situation than Gwen, who is carrying a pistol to defend herself against the Green Goblin.
Spider-Man using his belt to save MJ is the perfect choice as he recreates his stand with Gwen and shows that if he had the chance to save her today, he'd be perfectly capable of doing so. While this knowledge in itself is tragic knowledge that Peter Parker has to live with, it frames the moment not just as catharsis, but as progress. The loss of Gwen made Peter dedicate his life to preventing this loss from happening to anyone else, and committing himself mentally and practically to helping others. Saving MJ confirms that he's a better hero than he used to be.
Andrew Garfield's scene in Spider-Man: No Way Home was an epic moment of catharsis that was a long time coming, but save the original MJ for the comics was able to connect more with a different version of the moment.