Wow! Amazing thread. So many questions I don't know where to start.
I think the answer is yes, but they can't do it alone. Many people aren't even aware that UX even exists, much less how powerful it can be. I believe that that is the first step, educating people so that they are aware.
Remah's example about Three Mile Island is, unfortunately, a perfect example. As was said in a book club thread, "To design effectively, we must accept people for who they are rather than who we wish them to be." (I don't know if I'm quoting @docBOOM herself or if she was quoting Don Norman, but it's awesome!)
Whoever designed the switches and stuff at Three Mile Island obviously had no idea that something like UX Design was even a possibility. The good news is that people are learning, some faster than others, but they're learning.
I think that people like you are going to help people learn.