Playful thinking sets up questions in your brain that you wouldn’t have known how to set up just by explicitly trying to set up questions. A question is a record of a struggle to deal with some context. These questions, like the dozen problems Feynman carries around with him, set you up to connect with new ideas more thoroughly.
Reminds me of Feynman’s story about how a plate got him out of a depressive funk. https://kongar-olondar.bandcamp.com/track/at-cornell-part-2