Naturally I can tell you only what my own expectations are as an interviewer, and I can only guess what other people might expect; but something I can share as a fact is that simply doing the work presented to me, using the skills acquired naturally through the course of my career, with no pretending or practice questions or memorization involved, got me a job at two of those tech giants.

That was many years ago; perhaps things have changed. All I know is that the picture of tech interviewing I see so commonly complained about does not match my experience.