Real expertise isn't a problem. A expert plumber is shown to be so by his actions. Nobody would install a leaky faucet and be able to call himself an expert.

An expert psychologist for example? Her patients can remain depressed, mutilate themselves, kill themselves and even kill others and yet she will remain an "expert" mostly on the basis that she was educated at a place that similarly ineffective experts have claimed is a good place for a psychologist to come from.

I suppose the trouble is experts by education got lumped in by experts by results at some point down the line.

here, have some economics experts:

https://www.americanprogress.org/issues/economy/view/

https://www.cato.org/research/growth-development

how big is the middle part of the venn diagram here?

being skeptical of domain-experts is only 'religious fervor' if the field is cut-and-dried. many aren't