Every DS could play the same games at the same level of quality. So, unless a kid really wanted a specific console feature, it didn't really matter if you bought the wrong one.
Xbox is the opposite, if you get the cheaper console games will look worse and/or run at lower FPS. It only has one option for internal storage, leaving you with ~360gb after accounting for the OS, five or six modern games can fill that pretty easily. Official external storage costs about as much as the console itself.
For many people the trade-offs won't matter but it does make the PlayStation a much simpler choice if you're looking for a console for a kid that doesn't already favour one or the other.