I assume Google is looking for people who absolutely want to work at Google. Making the process cumbersome allows them to get candidates who stay at the company even if they have to do work that they don't like.

If that's what they're aiming for, evidence suggests that it isn't working - https://hackerlife.co/blog/san-francisco-large-corporation-e...

Many (as in 10-30% at best) perhaps. Not even close to half or majority though, so I fail to understand how the argument could be irrelevant.

At the beginning of 2017, ~12,000 of Google's current ~72,000 employees had previously worked at other big tech companies, and most of them were probably in their R+D headcount of only 27,000. I wouldn't be at all surprised if half of their engineering interviewees came from similar paying jobs, and a the majority of the remainder were college hires.

https://www.alphr.com/business/1005261/silicon-valley-swipin...

https://www.statista.com/statistics/273744/number-of-full-ti...

https://www.statista.com/statistics/219333/number-of-google-...