Dev-to-dev interviews for senior level positions at high profile organizations

Background: I'm a proficient programmer with extensive experience in my chosen ecosystem. I'm a hard worker, loyal, have a good work history, and can communicate well with others. I don't even have any problem getting work per se, I've turned down a few offers in the past months because it's not exactly what I want.

So, I'm ok with the idea that finding the right job will take time, but I've been at this for several months and I've done enough interviews that I feel like I'm seeing a quite-distressing pattern forming: specifically in my dev-to-dev interviews for senior level high-profile positions the person interviewing me acts in ways that are consistent with acting/feeling threatened, which in turn manifests itself as them actively/openly undermining and discrediting my qualifications and/or my work experience. My best guesses as to why these other developers are acting/feeling threatened come down to:

1. Because I am older than them (I'm 40)

2. Because they do not have as much experience as myself in an area, and somehow admitting this to themselves, which is not a big deal to me (it's not like I rub it in), would be a very big deal to them

3. Because they have to be the smartest person in the room and cannot abide someone else being equal and/or superior in any fashion

I don't understand the full extent of why this keeps happening, and even less sure what to do about it. I don't feel like I've been doing anything special to "deserve" this type of treatment, and imagine that it's pretty common stuff to have to deal with for anyone interviewing for these type of positions. I'm just hoping to find some answers on how to overcome this obstacle and get a good job at a good organization.