I’ve had third party recruiters contact me for Amazon roles, although I believe it was mainly sourcing and they passed you off to an internal recruiter if you got past the very basic sourcing screen. Apple, Google, Meta, and Microsoft were all internal-only in my experience.

with the the roles of recruiters being so metrics driven, most recruiters seem to be optimizing for funnel metrics. FAANG or not. But especially at FAANG where the number of recruiters and candidate pool is large that they prefer metrics.