As you recall everyone here is spending their own time to answer questions without any personal gain (some satisfaction in my case). Just by the nature of online communities (and Biostars particularly wants to be open/low barrier for new users) we get a lot of questions from new users that are either incomplete/repeats or from areas where we may not have any experts to answer those questions. It is best to leave those questions unanswered rather than have questionable answers that don't benefit anyone.
We can only have a vibrant community when there is a good balance of providers and consumers (have you been both?). There is no way to control that mix.
We have had many discussions about this in recent past and there is no one magic bullet to fix some of these issues.
I think most unanswered posts are from unanswerable questions. And even then, in general there are lots of comments trying to get clarification.
Your post, for example, ticked people off and got answers, but in fact it is not a good question. How did you measure this claimed declining quality? How did you measure the lack of contribution? Did you use some software, or just eyeballed? Did you check the quality of unanswered posts over time to back your claim?
So far, it is like an "I mapped my reads to the genome but my file is empty, what is wrong dudes?" question. Ok, it is a forum post, but even so, sounds more like ranting or trolling than a helpful post.
This is maybe a recurring discussion, see: Is The Biostar Fading? (Updated For 2014) and responses, unfortunately, the blog posts are now made private. BioStars is the most active community. Also, the OP is not constructive, as others have noted, please edit your question to make some suggestions on what to change.
Please also note that your post was sent, overlapping vacation and week-end in some time zones. You can't expect to get an immediate response on saturday/ friday night, even though you got comments quickly.
There are other sites like the public beta on SE: https://bioinformatics.stackexchange.com/ (280 Q's total and 225 visitors/day as of today, which is much less than biostars has per hour). The community overlap, but they have ~95% answered.
Quora bioinformatics: https://www.quora.com/topic/Bioinformatics, (2.8k Q's, don't have visitors stats?), as I see it, most of the questions there are more open ended and would not be a good fit here.
And of course :http://seqanswers.com/ for sequencing, focus on sequencing, with an old-school forum UI, you name it.
There may be a timezone effect as well: in the morning, Japan time, I see a lot of unanswered questions, which is not surprising since much of the Biostar community is asleep. Conversely, if I ask a question at work hours, Japan time, I have the impression that first nothing happens and then it tends to get buried quickly by the peak of activity when the European and the Americans get on line, and therefore misses chances to catch attention. Well, c'est la vie...
I wish I could upvote or downvote answers. The star rating of an author shouldnt only be determined by the number of posts but also the quality of the posts.
If you determine the star rating of an author purely by the number of posts, you are incentivizing more posts, and disincentivizing people for giving detailed answers to hard questions..There are so many amazing posts here.. I think the people who post these should be incentivized more to do so..