Even if they also put in the effort, doesn't mean it's worth it.

When interviewing for a FAANG, I had 13 hours of video call interviews with different people ranging from HR to managers of different teams. I was then invited to fly over to the US for formal interviews, where I had 3 days of interviews with different teams, about 5 hours each day (not helped by the fact that they had 3 teams interested in me, and they all wanted to go through their full interview process separately).

When I got back home, I then had another 3 hours of phone interviews for some reason, one of which was "from a manager I'd be working with extensively if I got the job" (I got the job, and in 2 years never even spoke to his team once).

I later learned that I'd aced all my interviews and they thought I was perfect, and they still insisted on yet more phone interviews even after 15 hours seeing me in person. The irony was as the HR manager was arranging the last one, I was very close to saying "if they still haven't decided after this many interviews, I'm not sure one more is going to make any difference, so I'm not doing it".

I actually wished I had refused that last interview because I got the job and hated it. Every other job I've had has required at most 2 one-hour phone interviews or 1 one-hour phone interview and a couple of hours on-site interview, and every company I've worked for has been better than that FAANG. For me now, having more than 2-3 interviews would be a major red flag.

There's some research that the bulk of an interviewer's impression of you is made in the first 10 seconds of meeting you, and the rest of the interview is just finding evidence to support that decision, good or bad.