Even if all the information you post is freely available on the internet - by compiling it in a post and spreading it, potentially even translating or interpreting it, you are still effectively doing the job of an opposition intelligence gatherer for them, for free.
The more places this stuff gets posted, the quicker it is to find, the less likely it is to be missed, the less time is spent looking for it. Obviously, aviation related information tends to be as time critical as it can get.
Acting as a literal resource for a hostile power, even if only in a minor role. I don't see any way to justify that.