Yeah, that sounds like a textbook conspiracy theory.
more of a pamphlet conspiracy theory, I wouldn't even really say that the claim is sequitur to the subject and they've avoided clarifying any orientation, though you can tell from positioning of bad faith accusations of anti-science, that this is a far right pamphlet.
Worth saying, you don't discredit a normal scientific theory, you dispute and disprove them. Discrediting is usually for things like Orgone Energy or this conspiracy theory, which are at best deranged and at worst deceitful. Strict Linguistic Relativism is generally accepted as not accurate, as not doing a good job of describing all cognition or enabling hypothesizes that generalize well themselves, but there is also evidence that it's not completely detached from reality. In weak forms it has it's uses, it reflects something true about the human experience; but in it's strict form it is easy to find counter examples.