On Puzzling, I noticed first that there wasn't an option to protect my own questions. I brought this up in chat, and other high-rep users replied that it has disappeared for them too.
Not sure if this is just Puzzling, or site wide, but I have just under 16k rep and have had the privilege a while. It's odd it just disappeared. Users on Literature have reproed.
EDIT: It's all questions, including 24 hour old ones with new user answers. Random example that has no protect option for me.