While I definitely understand and can relate to how frustrating it can be to be interacting with someone who is incredibly black and white, won't budge on anything, is very much in their own bubble, etc etc, at the same time I don't actually think being super open-minded is an incredibly glamorous desirable thing either. I mean at the opposite extreme you have someone who is so bendable that they almost have no identity or personal values/opinions at all. Sure this can make for interesting discussions but at the same time this person can also be targeted by those who want to take advantage of that malleability (/ negative spin), or they have difficulties making any decisions due to their 'openness'.
Anyway, I'm probably kinda in the middle. I can be insanely stubborn, because I do have strong values when it comes to some things (for example: nature/environmental stewardship/ not exploiting the land), and I really am not interested in 'exploring' the opposite side. Or I have my own beliefs around more philosophical/life views and perspectives, and while I can certainly listen to others and appreciate other viewpoints, I'm probably not gonna shift a whole lot since I've put lots of thought into why I believe what I believe, etc; but nor am I out trying to convince others either in some debate (I'm not a debate person). So, yeah. At one point in life, when I was younger, I think I thought it was a super negative thing to NOT be open-minded... but I'm kinda shifting as I get older and I am o.k. with being stubborn and set in some of my opinions and such.