Near the end of Avengers: Infinity War, after Iron Man receives a tremendous beating from Thanos, Star-Lord shows up just in time to fail to save the day, or his erstwhile ally. Considering that Iron Man has just been pummelled, bombarded, and impaled, Peter Quill’s voiced concern – “Did we just lose?” – seems somewhat cold, considering that Iron Man is badly bleeding, slumped in front of him. While it is true that there was brief antagonism between the characters, it should be noted that almost all of Star Lord’s usual teammates have fought with him in the past, with no lasting hard feelings. So why does Star-Lord seem so unconcerned?
The answer may lie in the very friends and allies that Star-Lord typically spends time with. A variety of exceptionally tough members of some of the most resilient alien species in the MCU, both the Guardians of the Galaxy and Yondu’s Ravagers can take a beating and still be reasonably active thereafter. Quill himself is half Celestial, sired by Ego the living planet, and has survived exposure to hard vacuum, the rough-and-tumble life of being a scavenger and a pirate, and direct contact with the Power Stone, an infinity stone that gave off almost uncontrollable force, tearing apart many of those that had attempted to handle it unshielded.
In the first part of the fight with Thanos, Star-Lord may have seen Iron Man taking a few hits and continuing on without much apparent injury. Using the Mark L armor which was composed of nanomachines, Stark first took damage to the ablative armor which protected him physically and kept him in the fight. Constructed with the assistance of Wakanda and Black Panther, the nanotechnology armor was a huge leap forward that could well have given Star-Lord the impression that Iron Man was, if not winning, at least holding his own. Since Star-Lord would have had no exposure to Earth humans in a combat situation before encountering Iron Man, Doctor Strange, and Spider-Man, his impression could easily have been skewed.
In Guardians of the Galaxy, Star-Lord survives direct contact with the Power Stone, which was used in Iron Man’s beating. In Guardians of the Galaxy Vol. 2, Star-Lord is actively skewered with energy by Ego, and in both cases, he is able to walk away from it, albeit with some difficulty. Although Peter Quill knows that he is not entirely human, a lifetime of perceiving himself to be of human stock could lead him to believe his resilience is typical. Combine that with Star-Lord having just made a defining mistake at the start of the battle due to extreme emotional distress, and it becomes easier to understand why he isn’t as aware of the situation as he might otherwise be.
Whether Star-Lord didn’t perceive the amount of raw damage that Iron Man had taken, or whether he had the mistaken impression that Iron Man might simply be able to walk off the injuries, it seems much more likely that he was mistaken than callous. Although somewhat self-absorbed, Star-Lord is not typically characterized as being cruel or cold – when combined with the recent discovery of the death of Gamora, it seems almost certain that his clueless comments at the end of Avengers: Infinity War were in error rather than malicious.