Google SPM / GPM hiring?

I am curious to hear from anyone who joined Google as a a Sr PM or Group PM. I previously had informal chats but never interviewed.

My experience: I had been put in touch with a Director PM in whose domain I have expertise (I reached out to his boss, also a Director, on LI). Had two informal chats. We initially discussed that I'd likely be targeting GPM. Then spoke about a specific role that was SPM. But it was filled by an internal candidate before I could interview. All within 2-3 weeks.

1. Are all PM hires at this level specialized?
2. What teams likely to value enterprise systems and SaaS experience? (analytics, ad tech, CRM).
3. I believe hiring a t this level is done by dedicated "exec" recruiters?