It opens up for these fringe movements is to present themselves as scientific, since they too have papers they can point to, and arguments that mirror the form of the scientific establishment.
The way to beat them is to be very clear about the limitations of science, and stop trying to misrepresent it as having a larger degree of certainty than it has. Science is demonstrably wrong sometimes, especially early research like the stuff that was circulating in the beginning of the C19-pandemic, and to make matters worse, a large part of science is dedicated to identifying instances where science is wrong.
That clashes with the official message is "trust the science" and makes devastating ammunition for undermining its credibility, especially nowadays when it is very easy to go back and check what claims were made in the past against which claims are made today.