> I generally urge people to think of this as a cooperation exercise and not a power struggle.

Any "adversarial interview" techniques are a big red flag, imo. They also make it easy to quickly recognise places with a toxic culture, so there's not need to beat yourself up if you fail. You dodged a bullet, plus now have an excuse to rant with your friends over a pint!

Hence, my favourite interviews (regardless of the side I was on) were the one when we had a chance to spend a day working with the candidate.