It's only logical- the people best suited to write articles are people who are well-versed in the subject, and the core community can't possibly contain experts on every subject.
I'm not sure that is always accurate; WP simply summarizes content available in reliable secondary sources.
For most topics it is possible to do so without expert knowledge. Of course; some areas have always needed experts to write. I'd never touch a medical article, or macro-biology, for example as it is all double dutch to me :) But, say, history is often easy to write if you have the source material.
For most topics it is possible to do so without expert knowledge. Of course; some areas have always needed experts to write. I'd never touch a medical article, or macro-biology, for example as it is all double dutch to me :) But, say, history is often easy to write if you have the source material.