Is this functionality available? If not, has it been considered already?
Only mods and developers can operate on frozen chat rooms, and only they can delete rooms (that answer is a year old, but I don't think it's inaccurate). This holds true even if you're an owner of the room.
Here on Meta, I can read the contents of frozen and deleted rooms (assuming the room isn't private), but that's it.
I think this behaviour is appropriate -- moderators should have ultimate control over this state of a chat room. If a room owner was allowed to override this, that would be akin to allowing a post owner to override a moderator lock on that post, which doesn't make sense from the perspective of moderation.
The only thing that might be a bit annoying is the auto-freeze after a week of inactivity. But on balance, I think that's alright to keep the chat room list cleaned up.