For the purposes of this discussion, I interpret it as similar to the common "I am not a lawyer/doctor/scientist/... but" disclaimer. More specifically, I might

For the purposes of this discussion, I interpret it as similar to the common "I am not a lawyer/doctor/scientist/... but" disclaimer. More specifically, I might paraphrase as "unusually intense spectator/armchair scientist"—someone who's read about the topic in depth but isn't a researcher/practitioner, so the commenter's understanding is indirect or anecdotal and hasn't been reinforced/validated by writing research papers and subjecting them to peer review.