The former project lead (Sam Bauers) mentioned 8 months ago that bbxf had been removed from bbPress:
https://bbpress.org/forums/topic/bbxf-%E2%80%93-bulletin-board-xml-format#post-35941
That’s the last official word I’ve heard on bbxf… but one note: the earlier discussions off bbxf mentioned it as a “bundled plugin”, not as part of the core.
https://bbpress.org/forums/topic/bbpress-initiates-importexport-standard-for-web-forums
I think bbxf is a great idea as a bundled plugin and should be revisited
It looks like this is the latest 1.0 alpha to include the importer and exporter:
https://trac.bbpress.org/browser/tags/1.0-alpha-6/bb-plugins/bbxf/
Sam mentioned in that earlier link that he’d rather have the importer/exporter based on RSS rather than a custom XML format… I think that’s why he actually removed it.
That said, you’re welcome to try out the bbxf plugins! It’d be great if someone could test them out and report back if they work or not!