The problem that I currently see rampant is that “definite proof” is hard to come by. There are a lot of people that use a set of alternate facts and call these definite proof. I’m afraid that with some people, I’m no longer arguing about how to interpret certain data, but we’re on a level where we cannot even agree that we are observing the same universe. And I honestly don’t have an answer to that problem.
Second to that: Data can change as we gather more knowledge about something. Covid is a prime example - in the beginning, very little was known. Some theories turned out to be mostly true, others didn’t hold up. Some advice was sound, other not. Still, some people point back and use the evolving knowledge as argument that nothing is knowable and we shouldn’t do anything.