bbPress.org

It’s been discussed a couple times:

https://bbpress.org/forums/topic/anonymous-posting

https://bbpress.org/forums/topic/anonymous-post

https://bbpress.org/forums/topic/my-manager-wants-to-remove-the-need-for-passwords-altogether

I would just make them register. If they can’t be bothered with that, why let them bother you with support questions? Can you think of other places where this is allowed?

Heck they can just register with a fake name and disposable email. It’s not that big a deal.