Sincere question: why be forthright in the exit interview? I’ve always politely left doors open.

I have no idea why someone downvoted you. Keeping cards close to your chest in an exit interview seems like a strategic move. Sure, you can sugar coat and hint at things that can be improved, but why spell that out? It might clear things up, but it might just make you look picky and high maintenance, closing the door on a future working relationship.

And it’s very unlikely to change things for those still stuck there anyway. I can’t think of an upside to being honest in an exit interview.

The concept of exit interview feels strange to me, as European.

Most to the time one just needs to give HR the resignation letter and that's it.

If one has enough vacation days to fill up the notice period, they don't even need to show in the office again, if they feel like it.

Naturally everyone will want to know why one is leaving, including the boss, but one isn't required to hold such conversations.

I feel you can be more honest -- while still being polite -- in an exit interview, since your alternatives are no longer hypothetical. If you have a competing offer on the table that pays 50% more, then you are no longer demanding, you are informative.

I haven’t ever had feedback about a company which I could both politely give and hadn’t already given directly to my manager (and other coworkers) before leaving the role. What does HR need to hear that’s both appropriate to say and not best told directly to the team?