Agree 100% with this - I think in general people really like to talk about what they do, so if you come to them with an attitude of curiosity, they'll teach you a ton. I've had maybe a dozen people over my career ask me about what a PM does/how to become one, and I'm always happy to chat about it. In a few cases, I was able to get that person some involvement with the PM team (as an example, a couple were in customer support and became the support/PM liaison, who would present all the data on trends in customer issues to us biweekly).

But you do have those empire-building types who see everyone as trying to encroach on their turf. If you run into too many of those, I'd honestly suggesting looking for a new job - companies where a lot of people have that kind of attitude tend to be both not great to work at and also less than successful in the long run.