The point is Semmelweis, whose information saved huge numbers of human lives, would be lumped in the same category (“toxic”) as your theoretical example, on acc

The point is Semmelweis, whose information saved huge numbers of human lives, would be lumped in the same category (“toxic”) as your theoretical example, on account of Sammelweis being considered rude and disrespectful. In simplest terms, ideas that threaten orthodoxy can be considered rude and disrespectful, and thus “toxic”. So perhaps the definition of toxic needs more refinement, or toxicity isn't the right thing to be looking at, despite it sounding about right in everyday conversation.