That's true, usually you shouldn't have to do that, because unfreezing a room really has no point if you do it just for the purpose of unfreezing it. Such an example would be important here though, because it should indeed be sufficient. Posting a random message to delay the freezing is not always sufficient, if my memory serves me right (I don't have an example off hand)
After all, anyone with 100 rep could just create a new room if the existing site room(s) didn't fit what they want to talk about. If you're trying to revive a community's conversation, that's great, but just unfreezing a dead room won't get you there. Not even you really cared about the room. It would be nice to have this because it doesn't involve me having to actually enter the room and post a message (not that it's hard) and can be handled from the access tab. In particular since, as you said in a comment I'm not seeing the reason for unfreezing it.
Then what was the reason? The room was dead for two weeks, was auto-frozen, nobody cared for 3 days, you unfroze it, and that was it.
I wouldn't have unfrozen it without a reason.