It's interesting that the paper mentions Andy Clark's work and hallucinations in separate threads but doesn't connect Anil Seth's introduction of controlled hallucinations and Andy Clark's work on that topic:

https://www.technologyreview.com/2021/08/25/1032121/brains-c...

I had always conceived of metacognition as genetic, given my own phenomenological experience dating to childhood. It wasn't until a colleague challenged this idea a few years ago at Carnegie Mellon that I'd even considered that metacognition may be taught and learned.