Leave your house's front door unlocked and keep a camera outside trained on the door. For the first week, tell nobody that it is unlocked. For the second week, tell everyone you meet that it is unlocked, and provide a map. On the third week your camera records someone going into the house.

Did telling people your house was unlocked make your house less secure?

Your house was exactly the same in the first week as the second week. Telling people it was insecure did not make it insecure - it was already insecure. You left it unlocked.

So it follows that if knowing some piece of information does not reduce the security of your system, then it is not sensitive information, and can be released publicly. On the other hand, if you don't know whether a piece of information reduces your security, you should probably find out. And finally, even if you never release information, that does not mean your house is locked up. But it may lead to a false sense of security.