It is much more important for a company to filter out likely low performers than it is to avoid filtering out likely high performers, because the costs of hiring an incompetent person are enormous. Not only do they not produce as much, they eat up others' bandwidth by asking too many questions, implementing super buggy code, or not communicating effectively. They make other people on the team feel like they're not pulling their weight. They're a pain to fire depending on company culture and laws.
This process is designed to overfilter and maintain an A-player roster as much as possible, vs putting butts in seats. It's hard to tell whether the pool is exhausted here - by some indications, there's a lot of attrition but also a lot of hiring...