Trust is not a binary thing in this context. It is OK to believe that one source is more credible than another, and as such is more useful for guiding an opinio

Trust is not a binary thing in this context. It is OK to believe that one source is more credible than another, and as such is more useful for guiding an opinion, while still being aware that it might be wrong or misleading. This is inevitable in a society that deals with too many complex issues to be an expert on everything yourself. An extreme example: I do not, as far as I am aware, know any of the contributors to the most recent IPCC report, nor am I qualified to independently assess its correctness or able to reproduce its underlying experimental evidence. Does this mean I should not be concerned about the effects of global warming? No, because in the absence of any better sources, the IPCC report is the most credible material I have available. The key thing here is that I am trusting the authors to be authorities in their own field of expertise. The appeal to authority fallacy is more like trusting Prof Sir Cumulus McCloud, who is a Nobel laureate for his research into a mechanism for global warming and the lead author of a large section of the IPCC report, on the best way to make cupcakes. (That is, while it is fallacious to assume absolute truth based on authority alone, granting some credibility in proportion is not unreasonable. A different type of fallacy, sometimes called appeal to false or undeserved authority to distinguish it, is relying on authority in one field to establish credibility in another.)