Which part? At first, it seemed like a bunch of baseless claims but when I clicked on the blue hyperlinks, seems he outlines some of his methodology and lab tests.
It’s too long so I only skimmed a bit but a lot of these types of rants usually end up with a suggestion to simply use sodium thiosulfate and save money.
Thinking back to when DeChlor, in the bluish-green bottles, was the only water conditioner sold at the LFS, he might have a point since i never had an issue using that stuff and it was just sodium thiosulfate.
Flash forward decades and now I only use Prime, and I’m not sure why or how I got here. Was just told it’s better and safer but truth be told, DeChlor always worked fine.