Do you have anyone in mind?

Actually, are there any scientists with non-negligible power and influence these days at least in their role as scientists?

(Note: Fauci would be a good example of someone with a good deal of power and influence, who has a scientific background, and who has routinely over-stated certainty of various matters, but this is explicitly in his governmental role, where, alas, very little space is given for being uncertain but doing our best. I fault him anyway, because he knows better, but not nearly as much as if he were in a purely scientific role.)