> why some people are incapable of changing their point of view

I've thought about this and the conclusion was:

What you believe you know makes you what you currently are. You can't just believe in a contradictory position. You could believe that you have been proven wrong, which would then change your belief.

Changing your point of view, looking at things from the vantage of someone else with different life experiences and the resulting belief systems would be dishonest at best, and claiming that you are capable of changing your beliefs on a whim is like being able to rip your arm off.

You can, at best, adapt your own belief to encompass theirs with caveats or simply not care about your truths.