RE Query allows for greater flexibility in the output of fields from RE than the List option does. For a client with an email connector, who may be using cons codes, solicit codes, attributes, etc. to segment their audiences this isn't possible with the List endpoint in RE NXT.
Thank you for this idea. We communicating user feedback regarding this need with Blackbaud. Currently Blackbaud's list endpoint is much more limited than Query. I would be interested to hear from other users regarding the various filtering needs they have.