We somewhat established non-experts are welcomed here. Of course there is a good chance that 'consensus' mainly originated from this site having more non-experts than experts.
Is this a problem?
This is really difficult to analyze. In its current form this site is trying to be open to experts and non-experts alike. Does the presence of the non-experts drive away the experts? If this would be true, eventually we would only have non-experts on the site, and nobody is left to answer questions correctly. That would be bad.
However, as long as the community is able to distinguish between bad and good posts, which is something we all can do, I don't see a real problem. We might have a limited amount of experts at first, but we are still growing. If we were to decide only professional initial research would constitute good initial research, we would scare away all the non-professionals and we would have a considerable smaller user base. I feel it is more important to have an active site with valid content (professional or not), than to have an inactive site with solely professional content. Wouldn't an inactive site drive away professionals just as well? As long as we can prevent inaccurate posts from filling up the site, we should be fine.
Required initial research
In line with the points I raised earlier: I feel we shouldn't hold up every question to the same standards.
What I am about to say is very much in line with the FAQ. Mainly the following two points which I've noticed tend to be a problem with the questions being closed on this site.
there is no actual problem to be solved: “I’m curious if other people feel like I do.”
Initial research should resolve this issue. It should be clear there is an actual problem. What is it that you don't understand, and how would an answer to your question help you? Just stating facts and asking an open-ended question (or no question at all) isn't answerable. You could give tons of relevant information, but that is not a good fit for Q&A.
we are being asked an open-ended, hypothetical question: “What if __ happened?”
This is our main problem. We should make it very clear that although non-expert questions are welcome, we shouldn't allow questions which aren't founded in any way. Even non-expert questions shouldn't be hypothetical. Stating you heard something once, but don't recall when or where doesn't constitute a good question. Non-expert and expert questions alike should show proof there is reason to ask the question.
The difference lies in what proof. If a non-expert can link to dozens of articles/forum-posts/TED talks and the like, there is reason to believe his question is founded. There is nothing wrong with being skeptical and asking for more scientific resources. They usually don't expect a very broad answer, just a push in the right direction so they can attempt to look into it themselves. This will guide them into self-learning and being able to ask a more professional question on the topic the next time around.
Adjust your answer to the level of initial research
This leads me to a tip for those answering questions with non-professional initial research. Don't answer them as if it is a professional question. Just point them in the right direction. My guess is it constitutes a good answer just as much as a more extensive answer would. Save your time for the more detailed questions.