Seems to me that there are two factors.
First, I read that the best mine and source for high quality mica is exhausted.
So, the mica available now is not as good as it once was.
Secondly, mica generally speaking does not translate to SMD, which is where the quantity business is for component manufacturers. So, it's a low volume biz, which means high prices.
And third, as mentioned ceramic does not require mica at all, and can be made in labs/factories.
Seems to me the wikipedia account is erroneous, but there is a requirement for a citation for what is written - of course that source can be utter BS too.
_-_-
It can also go too far the other way. Since anyone can edit it, there are a few people making impertinent calls on the validity of subject matter for which they have no understanding. I've seen arguments in the backside of WP against an external link to a properly referenced document for no other reason than that the document's author was an amateur researcher and not a professional author or a scientist. A bit of Animal Farm goes on there.
Improvement of WPs curation is important -obviously it caused some surprise, but the facts about the caps are more important. I don't find them too costly where they are really needed. It's a shame about the Mica situation.
