Fortunately, Iron Man's technological adaptation of the Regeneration Cradle was powerful enough to heal his wounds so he could survive the wound until he got proper medical care once he was back on Earth - because without it, he could have well died from blood loss then and there.
How did Tony Stark remain alive after Thanos impaled him with his own iron suit, in Avengers: Infinity War? Nanotechnology. The suit Tony uses in Infinity War is based on nanotechnology, and has a characteristic "seething" quality as it builds or reconfigures itself.
The important part of this insight, however, is that if Thanos always kept his word, then when he performed the Snap, he likely did indeed exempt Tony from it specifically since he had told Strange that he would spare Tony's life. That bit of honor proved to be his undoing.
Would Tony Stark have been able to snap the gauntlet and survive if his suit had been made entirely of vibranium/uru? No. He had to be connected to the stones in order to use them and that connection would kill him if he used them all at once.
Throughout the course of Avengers: Infinity War and Avengers: Endgame, Tony Stark's life was spared on a few occasions. This happened when he survived Thanos' snap, but Doctor Strange also ensured that he would live to experience that moment.
Stark's resistance to the Mind Stone likely stemmed from the new element he created to power his arc reactor in Iron Man 2. Needing the new element to save his life, Tony uses Project Pegasus' resources for help, the same organization which was created to wield the Tesseract's power.
What did Tony Stark see when he snapped his fingers?
After Tony snaps his fingers while wearing the Iron Gauntlet, he's transported to a mysterious place. As he tries to gather what's going on, he hears a voice call out to him. Tony turns around to see a grown-up version of Morgan, played by Langford. Tony quickly realizes the young woman is his daughter.
Yes, it is true that Hulk was trying to survive while Tony succumbed to death - but Tony had little visible difficulty because of one main reason: His armor. Mortals are unable to wield any single Infinity Stone, let alone all six. Ronan confirms this when he tells Quill as much.
After saving the world, making a play to sacrifice himself, and defeating Thanos' army, he was not able to lift Mjolnir in Age of Ultron. This shows that being a hero and doing occasional good deeds does not make you worthy. Tony wasn't a bad guy per se, but certainly not his best self yet.
When it was suggested early on in Tony Stark's time in the MCU that he get surgery to remove the shrapnel from his chest, he was decidedly against this. He found out that he would pretty much instantly die if such surgery were performed. Because of how the shrapnel had entered his body, it was impossible to remove.
The final battle between Iron Man and Thanos in Avengers: Infinity War secretly proved just how much the Mad Titan feared Tony Stark's armored Avenger.
When it comes down to it, Thanos knows Stark as the man who thwarted his efforts to take over Earth via Loki in 2012's The Avengers. "Which is why he's aware of Stark from the original Battle of New York as the person who undid the plan," Joe Russo said, giving extra meaning to Thanos having respect for Iron Man.
When Iron Man was beaten, Thanos tells Stark that he has his respect, and that he hopes Iron Man will be remembered after Thanos succeeds in his twisted mission.
In Avengers: Endgame's climactic battle, was Thanos really trying to rip Iron Man/Tony Stark apart in half? Well he almost did. This scene was a brilliant callback to the comics where Thanos picked up Iron Man and just ripped his body into two. Just look at Tony's spine coming out of his body.
In the end, Tony Stark snapped Thanos and his army out of existence and dies because of the irreversible damage his body has suffered from the Infinity Stones. When Tony snapped, he, ever the wise-cracker, replied to Thanos' “I am inevitable” line with his own mic-drop, “And I am Iron Man”.
Unless he has excellent magic powers like Hela, (which he doesn't), he is going to get pinned down by Mjolnir. Even the mad Titan won't be able to get up if he is pinned down by Mjolnir.
Thor insisted that he wanted to do the snap and begged his colleagues to allow him to do it so he could contribute to the cause. However, they collectively decided that the God of Thunder wasn't right for the job.
Mjolnir has been manipulated in different ways in Marvel Comics, and many years ago, Iron Man was able to hold the hammer… thanks to zero gravity, meaning that he didn't properly lift it and he would have still not been able to wield it on Earth because he wasn't worthy.
Even so, it seems unlikely that Thor would have been incapable of using the Gauntlet. In Infinity War, he endured the power of a star to forge Stormbreaker and came out with no significant injury that could hinder him.
We know that Gamora wasn't at Tony Stark's funeral - unsurprising considering that she didn't know him, really - so she must have fled after the battle was won.
On Earth, the Snap led to a five-year period in which the world fell into societal collapse and many countries abandoned their national borders. In 2023, the victims of the Snap were resurrected by the Avengers, after they went back in time to alternate timelines to acquire their own set of Infinity Stones.
According to the Eternals, the Hulk's snap released so much energy it was able to cause a mysterious cosmic event called an "Emergence," while Thanos' did not. It seems the Hulk's strength should not be underestimated, because his feat was much more impressive than Thanos'.
