My first thought was to vtc this post as a possible duplicate to the already well discussed posts which, even though took place almost a decade ago, still are in complete relevance.
In any case though, large swath of unanswered questions has been a headache not only for this community, but it is rather a network wide issue.
I'm wondering if this reflects badly on CV compared to other SE sites.
I don't know about the current standing of CV among her other sister communities. But we can all agree that no one would love to see hundreds of questions, that have genuine well-researched queries, lying unanswered in a dark corner.
I'm also wondering if there is anything we can do about it.
Peter, as far as reducing the number of unanswered questions, there is no radical overnight approach. You have to resort to the old means, discussed both here as well as in other SE posts- the most prominent ways are closures and answering (nodding to kjetil's comment).
$\bullet$ Closures Let's face it: one can count by the fingertips the number of folks who volunteer in clearing the review queue along with the mods. We need greater participation from the community not only in the review queue but also to search for old questions that can be closed as dupe/low quality/programming based (there are many which escaped the vigil eyes back then).
$\diamond$ If you see a question already has been answered completely or there are few hints which you can compile as an answer, then please go ahead and make an answer (referencing the said comments and if it is verbatim, then as community wiki).
$\diamond$ If you can provide at least a comprehensive partial answer, then again don't hesitate to jot down one.
$\diamond$ Find it interesting? But you can't provide the answer? Then provide bounty to promote it.
$\diamond$ Edit old questions of your followed tags that you deem are good queries but otherwise missed the mark due to some unwise usage of ambiguous formalism into a more cogent structure. Trust me, I happened to edit few old posts that received answers subsequently.
$\diamond$ Share any such posts that you think deserve an answer among your peers, colleagues, professors. This, in turn, might initiate participation of new, experienced users.
Continuing the same point, I would add that at the end of the day, we need more answerers. So, we need more participation. One way is, as I wrote, to share the platform and spread the words in the forest.
$\bullet$ If there is already a good answer but not upvoted, then give a $+1.$
$\bullet$ Identify those tags that have the most unanswered questions. Try to pinpoint any possible reason or so. Every tag has a batch of top answerers. Why didn't they answer? See if you can find anything and address the same.