This isn't about going in for a one day interview. It's about the huge amount of time required for the interview preparation that comes long before an actual interview. As the post I replied to said:

> even if you were to ignore the upfront preparation costs just the timeline (months with not much indication)

And the fact that it isn't just one day of interviews, as the post details it's multiple interviews, some remote, some in person.

All of these things are an absolutely enormous time suck.