I have been getting this message consistently in my applications that use the Photos framework (import Photos). It does not seem to impact functionality of the apps. I see it when running on the Xcode simulator and when running on actual devices and in both production Xcode and Xcode Beta 6.
Just for fun I took a look at the runtime console log for a Photos app (PhotosDisplay) I designed while running on an actual device (iPhone X iOS 13.7).
The iOS system program accountsd logs “Unentitled access by client PhotoDisplay…”
And then PhotoDisplay logs “Error returned from daemon: Error Domain=com.apple.accounts Code=7”
While this does not answer what exactly is going on it does give some context that it is pretty deep in the framework and probably not something we can control.
Tom