I think this was part of the intention behind their attempt to give this film an argument. Thanos weighs the pros and cons, and decides that in order for the universal scales to be tipped back into balance, half of all life must cease to exist (Consequence: Becoming). He doesn’t stop to reconsider his plan. I think the OS problem is/could’ve been Consider, and the OS Solution is/could’ve been Reconsider.
Thor, according to the directors, “wanted to tell Thanos that he got his revenge”. A possible example of a Symptom of Feeling. All the characters in the story are feeling immense pain. And Thor’s Response to that is some sort of faulty Logic like: If I use Stormbreaker, I’ll be able to take Thanos easily and tell him that he sucks. He doesn’t really think things through again once he sets his mind to that.
Doctor Strange is one of the first characters to really feel the gravity of the situation, and he responds logically: he will not save Tony or Peter if he has to choose between them and the time stone. But in the end, he reconsiders, thinks things through again, and possibly through his action has set up a victory for pt2? (Story Goal: Obtaining. Holding on to/re-obtaining the Infinity Stones)
I think it could be possible that Avengers 4 will reveal or find a way to show: wait a minute, Infinity War isn’t resolved yet, and then finish up that story before possibly starting a new one. But if that’s not the case, then…
The truth is, for this film to have an argument, we’d probably want to have the statements the Russo’s made in their interviews to actually be in the film. Like, maybe freeze frame on certain key scenes and have them fill in the gaps of the narrative with Voice-overs, lol. Without that, and maybe even with that, the film is very likely broken.