Jeez. Should they not expect each interview stage to at least whittle down 1 applicant for every 2 that reach that stage? That's 4096 people who got to interview.

Or I guess they decided on a "mixture of experts" and put everyone through to multiple "final round" from different domain experts? All of whom are somehow adding value?

I don't think I've ever said this before, but that sounds like a job for a management consultancy.