Except that 99% of engineers aren't being hired by Google nor being paid on comparable levels.

So why is Google relevant to this in any way?

Perhaps. I'd even say it's part of what is taught as part of a PhD.

But if someone was ready for your exact question by having the right interview practice/experience, or they just don't care about your job so there's no stakes. Then you still aren't measuring what you think you are.