There are several implicit assumptions in your question:
- That Quora and SE have the same mission
- That page views are a meaningful measure of success (whatever success actually means anyway)
- That "no one" is reading aviation.SE
The page view points (2 and 3) are largely irrelevant to us as site users. Perhaps Joel and the SE owners care deeply about page views but for all I know they have other measures of success that are more important. And obviously, the idea that "no one" is reading aviation.SE answers is nonsense. You could talk about whether a lot of people are reading it or not, but that just turns into a debate about what "a lot" means, quality vs. quantity etc. which is rather uninteresting (to me, at least).
Anyway, the more important point is that SE and Quora are based on very different ideas about questions. Compare these quotes:
About Quora (my emphasis):
We want to connect the people who have knowledge to the people who
need it, to bring together people with different perspectives so they
can understand each other better
We want Quora to be the place to voice your opinion because Quora is
where the debate is happening
Quora provides a personalized feed of insightful answers to questions
you hadn’t realized you should ask.
About aviation.SE (emphasis in the original):
This site is all about getting answers. It's not a discussion
forum. There's no chit-chat.
Focus on questions about an
actual problem you have faced.
Not all questions work well in our format. Avoid questions that are primarily opinion-based,
or that are likely to generate discussion rather than answers.
Straight away, you can see that each site has a very different feel. Quora is interested in multiple viewpoints, contrasting opinions, cross-disciplinary topics and intellectual curiosity. Those are all great and important things, but StackExchange is based on the very different idea of helping people solve practical problems within one well-defined area. Those are simply not approaches that can be directly and easily compared.
There's a very nice and longer answer on Quora (!) that contrasts the sites very well, but I think this quote from it sums it all up:
It's not that one has more community than the other or that one favors
points more (they're both pretty good at both). It's that the hooks
differ. The hook at Stack Exchange is a pretty high level of assurance
of accuracy and availability of an answer. The hook at Quora is "oh
that looks interesting!"
The same question on StackExchange was closed as "not constructive", which is exactly what I would expect :-)