But for some reason, my first reaction to their earliest attempts wasn't to give them the benefit of the doubt–it was to immediately find problems and then dismiss their ideas.

The author is clearly questioning his tendency to judge and reject rather than observe and question further. forwardslash adds

I'm not sure if it's just part of the culture or something more innate to being human

I wonder too if the tendency to make negative predictions or assume negative outcomes - to judge/reject - might be

1. a consequence of the education of technologists and engineers. Note: my comment is just based on my own limited observations and is not intended to imply anything beyond that: I often find myself surrounded by graduates of MIT. They like to solve problems. They like also to predict problems. When it seems to me that more questions are needed to get a fuller picture, they are already engaged in imagining problems. Do you think that could be a cause? and

2. There is a tendency in our culture to assume negative outcomes over positive ones. Imagining positive outcomes requires cognitive complexity. By cognitive complexity, I mean the definition in the second paragraph here. Consider the statement: "The principal wants to see you in his office." -- If you are in high school and you hear that statement, who is going to think that the principal wants to see you to give you an award? Even the most praise-worthy, high-functioning, obedient student will shuffle to the principal's office grumbling, "What did I do? It's lies all lies. I didn't do anything wrong." In fact, the principal is congratulating you on an award. or

You are waiting in an airport departure gate. You hear your name called to come up to the desk. You immediately assume that you've been bumped, that they over-subscribed and you have to take the next flight, etc. etc. You can barely contain your frustration. You grumble something unkind to the attendant. She says, "Calm down. We've just upgraded you to first class."