And not just in one field! E.g. sometimes climate change denialists say that climate science is not even real science and that these people are just self proclaimed scientists. But the thing is that all fields of sciences (at least all natural sciences, engineering and mathematics) are interrelated. All of these have boundaries touching each other and all fields will have at least some scientists working on these boundaries with people from another field. So no field can simply fake it. In other words, basically everyone who has published in the past few decades will have a finite Erdos number :).
Also, not only you can trust the experts, but you don't really have any other sane/viable choice.
> I've seen this play out in companies; businessmen in positions to promote technical people, often making some very poor decisions.
This is true. What I say to people (small business owners or startup founders) is that you can't pick a co-founder, a tech lead or even a good subcontractor without having the technical knowledge yourself.
But that's pretty a different issue. First of all, here you need to pick a specific person for a specific role where you'll then have (want) to trust all (most) of their decisions and you don't have anyone to compare these to. Also, it's many decisions based on a small amount of data.
While what we are talking about is listening to experts who mostly say the same thing (the scientific consensus) and it's a very few decisions based on a huge amount of data (research, experiments). There are, of course, times when the consensus has not settled, when experts won't agree, but then you know that they don't know enough yet.