I don't have a strong view of the answer, but here are some considerations.
I believe that views that are generated by direct search are considerably more valuable than views that are generated by clicking through things in one's feed. Direct search signals a specific desire to learn about the topic, whereas clicking links in one's feed is a quasi-passive activity. Insofar as a fairly large fraction of Quora pageviews are generated by clicking links in one's feed, I believe that this points in the direction of Quora views being less valuable than Wikipedia views. For instance, an answer I wrote a few hours ago got over 400 views because somebody chose to promote that question. I don't think those 400 views generate social value that is in any way comparable with the social value that would be generated by 400 people searching for that question (or a related question) and stumbling on my answer in the course of their search.
Wikipedia is much more well known, so Quora viewers may be a more selected segment of the population, hence arguably may derive higher value per pageview than Wikipedia viewers. This argument points in the direction of Quora views being more valuable than Wikipedia views.
Wikipedia pages tend to be relatively more comprehensive and include a lot of citations. For somebody who wants to learn about a topic well, viewing one Wikipedia page would generally be more valuable than viewing one Quora question or answer. However, viewing all the Quora questions and answers on a topic may be more valuable than reading the Wikipedia page. The question talked about value per pageview, so in that context, I think this consideration points in the direction of Wikipedia views being more valuable than Quora views.
I'll add more considerations as and when they occur to me.