I would be very happy if Scrivener 3 could include a calender, where you can select any day from the past or the future and automatically takes the date as a header for a separate document.
This would be helpful e.g. for writing a diary, for documentation purposes, for daily protocols, for timelines …
If the main idea is to insert the date when you create a new item, that is a lot of programming and user interface to accomplish the result. Have you tried just hitting the return key to make a new item, and then ⌃F6 to Edit ▸ Insert ▸ Current Date & Time into the title field?