This is what happened: heroes about to win, hero gets angry and does something stupid, he fails and the stakes are ratcheted up because they would have succeeded if he didn't sabotage them with stupidity.
Even if the reasons behind this are more thought out than in most movies that use this trope, it's still a trope that we've seen a million times before and right now very few things pull me out of a movie quicker than seeing heroes do something totally goddamned stupid because the plot needs him to in order to ratched up the stakes. Just like in Logan, when they decide to visit the family. I would have absolutely loved the movie if they did not do that. Or, at least find a way to put them in the family's house that was the result of sensible decision-making and not completely fucking stupid and inexplicable.
The actions we see on screen, step by step, are completely indistinguishable from movies that phone it in with shitty tropes. I would have like to have seen something fresh, such as... Quill doesn't succumb to his emotions, doesn't do anything stupid, and they actually get the gauntlet off Thanos. Then Thanos frees himself as Strange powers up an extremely powerful spell, Quill sees that Thanos could regain the gauntlet and charges him with his guns while screaming about Gamorrah, Tony yells for Quill to keep his distance, Strange yells that Quill is going to get hit with the spell, and that split second is what Thanos needs to grab Quill, turn his blasters against whoever has the gauntlet and somehow regain the gauntlet in the wild scramble that follows. Someone yells at Quill: "Why would you do that? We had it!"
I actually really like the idea of Quill having the self-control to avoid creating the situation we see in the movie, only to have his emotions overrule his logic minutes later.
That's just a suggestion, but at least then it would be different than the exact same trope we see every single fucking time.