At some point, people invest into their work/employment so heavily and tie it to their identity tad too much, they internally need to feel this is the right and best choice, which for many top talents may mean working with "top 10%", whatever that means. So otherwise smart folks will start parroting official company policies and become a 'good boy'. Suffice to say I don't look kindly on this, but it highly depends on the business.

I've heard similar claims many times before, albeit mostly not from places paying so much. Ie at university, there was promotion seminar from Accenture branch in our country, the guy was some higher manager and stated the same, how they want only the best of the best and work hard getting and maintaining this. Then maybe 10 years later I had 20 of them as contractors and reality was not that rosy, huge variation from good to terrible.