(Mod hat off)
I didn't RP much in the latter half of the year, so I'm not all up to date on everything. I've seen some of Pyre vacuuming up members, and I suspect it is because people want to have fun and they are finding it there. That's a perfectly valid reason to join a corp. For some people certain IC things are a priority when looking at a corp, for others considerations that are not entirely IC might take precedence - I think whichever approach works for you is valid. The main thing is you are having fun when you log in.
I think that if WH corps decide they want to pursue an isolationist policy, that's actually kind of an interesting RP route to go down. It isn't everyone's responsibility to make themselves available for everyone else's RP. It has the benefit of being something it actually makes sense (potentially) for a corp in that position to do.
I have seen a lot of discussion about older RPers forcing new people out or discouraging them. I'm kind of curious about it. I am fairly sure that I haven't intentionally discouraged anyone (in fact, I try to encourage people when I can), though certainly there have been people throughout the years I declined to interact with because I didn't find interacting with them fun or interesting - and my position tends to be that while no one is required to RP with me, I expect that same courtesy in return (barring the more kinetic sorts of Eve RP, anyway. I haven't ever had someone I didn't want to RP with RP at me with guns, though. It's always been people I'm fine interacting with so far - which is always nice for the press releases afterward.)
Of course, I'm not plugged into every aspect of the community, but I suspect that the most common sort of exclusion is unintentional. Many players who have been around a long time know each other, and are comfortable with each other, and it can be intimidating or even difficult to break into an established social group as a newcomer. For that type of exclusion I don't know that there is an easy solution, other than encouraging established players to reach out to newcomers. I don't know that hostility toward those more established players is a useful tactic - but that's why I'm a bit curious. It seems like you are talking about something more intentional than just a lack of reaching out to newbies from entrenched social groups.