I considered it as a possibility and in the end it wouldn't matter too much I suppose, the more people who have the key the better in terms of anonymity, would be nice if it would stay closed for a while and people transferred the NFT to others as a way to distribute it.
Interestingly an unlockable text can be changed so the key could be changed but anyone who transferred or gave away the NFT would not get the new key 🤔