I just wrote (and submitted) my third short story in about a month: "MAXO signals: a new and unfortunate solution to the Fermi Paradox". It's a short-short (only 803 words long) for the new series of back-page hard-SF stories running in NATURE.
I'm now crossing my fingers and toes and hoping like hell that nobody else has written this particular story, because it's a blindingly obvious one-trick pony ...
Most of the convincing ones are, sadly.
Glen David Brin's review paper "The Great Silence" is twenty years old now, but still gives a good framework for all the different hypotheses extant then.
I bet they pay SF writers better than those writing scientific papers (who get nothing)!
Oh, but it is:
Under Martian Ice by Stephen Baxter
Undead Again by Ken Macleod
A Modest Proposal... by Vonda N McIntyre (my favourite of the ones that have appeared so far).
That said, that doesn't nesse-celery apply here.
On the third hand*, even if it has been done before - and this particular conceit is not a million miles conceptually from things in previously published stories from your own to A Fire Upon The Deep, there's precious little new under the sun†, and what counts, as you well know, is way you pull it off.
I'll stop teaching my grandmother to suck eggs now‡.
* Now which is scarier,
† Because, of course, gravitationally speaking everything is above the sun...
‡ Why my, or anyone else's grandmother, would want to suck eggs, is a different matter altogether...