Its complicated and not proven who the poster was or if he was connected to UWC at all, but the posts were moderately sophisticated, and seemed mostly focused on casting doubt on everything in the science thread rather than trying to find a scientific truth (in my opinion only, I apologize in advance if that is not a correct analysis).
He may have been genuinely curious in the topic and just came across oddly, or may have been more than that. It is very challenging and time intensive to explain away every random "explanation" that someone throws out, but he encountered a substantial wall of expertise from a sizeable number of expert chemists and other scientists that would not normally be found in an internet hobby forum. The fact that the alternative ideas did not take hold may have been why he lost interest.
Here's a particularly pointed exchange:
Courtney Aldrich said: Choline-based ionic liquids do not have any useful algaecidal activity for aquaria. Why not? Response: Choline-based ionic liquids have no reported potent algaecidal activity at low concentrations (below 1%). By contrast, polyoxetonium chloride is a potent algaecide with...
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