samursus
Explorer
It occurs to me that there may be opportunity here.
One possible reason for the lack of adventures is that WotC may be short on suitable material to publish - after all, if they don't have suitable submissions, they can't publish them!
That suggests to me that if you are thinking you'd quite like to contribute, now may well be a good time to get the Submission Guidelines and put forward some queries.
Of course, it's also entirely possible that there's some other reason at play. But, really, what do you have to lose?
You have hit the nail on the head with this one, apparently. In the very recent Mailbag article they specifically mention a lack of people submitting material to fill out a particular type of article that a player is asking for. They once again put up their email address for submissions.
(not behind the paywall)