Thanks for your feature request! @connor and I have discussed this a lot in the past.
One of the major reasons we have “Untitled” present on unnamed cards is that the platform depends on titles for main of the key interactions; this includes previewing (single-click on a card title), opening (double-click the card title), and dragging (to add cards in the pinned bar or inside other cards). These interactions are key to making Supernotes fast and intuitive, so we try to encourage you to add a title and expand on your thought and make it a permanent part of your knowledge base.
Titles are also used for the command prompt card search and parent / card links, so without them you won’t be able to quickly find / link those thoughts easily. We had tried to automatically create titles depending on card content, although it didn’t work as well as we thought it would.
This is an important UX, and we were are constantly thinking about ways we can improve it, if you have any further ideas or suggestions do let us know!