Not singling anyone in particular out but who is one to believe?
This is the quintessential post-modern question.
The question might be posed as, how do create, fund and operate truth producing institutions that can be trusted by the public.
When institutions are funded by the rich (e.g. corporations, share holders), there are good reasons to suspect that the message is biased towards the interests of the rich.
Public financing of truth producing institutions have the promise of producing truth for the benefit of the people using public funds, but when this is done through the mechanism of the state, there are reasons to suspect that the message is biased towards the interest of that state for the state's sake. If the state isn't democratic, then the state's interest is not the same as the people's interests.
The only reasonable path I see is to use public funding to fund quasi-independent truth producing institutions. The NSF and CDC are steps in the right direction provided the state can keep their hands off of them. Ditto the British and Canadian commitment to publicly funded independent press (the US PBS and NPR are largely financed by big money now).
Still... I think there is something deep in the human brain that biases large numbers of people to respond to fear by becoming more authoritarian in their world view. This authoritarianism can take many forms. I have an uncle with a PhD in Chemistry from Princeton and he's spend many hours (including a very uncomfortable 4 hour drive to Vermont) trying to convince me that the Earth is 6,500 years old - this based on the authority of his scriptures and the added ages of the people going back to Adam. Growing up in the church, I've been up close and personal with science denial my entire life and in all of the discussions and arguments I've been involved in or have seen, I've never once seen a science denier change their minds.
On the other hand, I've seen many, many different hair-brained wacky ideas and conspiracy theories sweep through churches and political associations like wild fire. I still recall the conversation with a life long friend several years ago who tried to convince me about "pizza-gate".
Masks and COVID-19 are a pillow fight compared to the coming epoch of climate disaster. When we're having serious discussions in public about who to believe, it's an indication that our culture is failing the test. I no longer hold any realistic hope for our species. Collectively, our brains aren't wired to make good collective risk decisions. Fear wins.