While argument from authority is often regarded as a fallacy, it is reasonable to consider an authorities opinion as evidence for a proposition. If someone is entirely unfamiliar with a subject, then expert opinion on the issue is a better default position than totally uninformed speculation. Due to variance in expert opinion, searching for the majority opinion is better than evaluating only one opinion. Only looking at one expert could be subject to cherry picking.
One can begin critiquing how expert opinion is surveyed. A survey could have sampling issues or poorly worded questions. A group of experts could be ideologically biased because only ideologically biased experts would enter into that field or there could be a tendency to have other beliefs that make evaluating certain beliefs more difficult. How the group of experts is defined could also be an issue. Consider the hypothetical example of the majority of Quranic scholars believing that the Quran is a completely accurate historical account of the life of Mohammed.
There will always be issues of sampling bias of expert opinion. However, it can provide a rough sketch of the reasonableness of certain positions. A layperson should consider expert opinion a moderately good default position. If an individual is not even familiar with why the experts have this opinion but they still reject it, then in all likelihood, the layperson is incorrect and ignorant.
Despite knowing nothing about climatology, I believe that the earth is warming. Despite knowing nothing about geology, I believe in tectonic plates. It is not reasonable for me to have expert level opinion on a variety of topics, so defaulting to the expert opinion is reasonable. The more common problem is when rejection of expert opinion is ideologically motivated as it often is. One can reasonably reject expert opinion but the burden of proof is on the layperson.
"If an individual is not even familiar with why the experts have this opinion but they still reject it, then in all likelihood, the layperson is incorrect and ignorant."
This might be true, but can you give any statistical evidence that this is indeed the case? Consider, for instance, these counter-examples:
Until ~1900 it would have been on average safer for a layperson to avoid doctors altogether.
Also, until very recently the doctors in the US were recommending that infants should avoid exposure to peanut to prevent future allergies. A layperson who was totally ignorant of the science behind this recommendation might still quite reasonably reject it by observing that kids in Israel are much less likely to have peanut allergy despite consuming lots of peanuts from the very early age.