The problem
The 4Ls format is popular because it covers more ground than a simple went-well/didn't-go-well split. Liked captures wins. Learned captures insights. Lacked captures what was missing. Longed For captures aspirational changes.
Four categories means four times the sticky notes, four times the discussion, four times the whiteboard density. And if someone takes a photo at the end, you end up with an unreadable cluster of colored sticky notes that means nothing to anyone who wasn't in the room.
The 4Ls format deserves a better output format than a JPEG.