Why do Jupiter models want fewer heavy elements than its atmosphere shows?
In plain words
The Galileo probe measured an atmosphere enriched in heavy elements, but many interior models that fit Juno's gravity need a less enriched outer layer. Either the models or the assumed relation between pressure, temperature and density of hydrogen-helium (the equation of state) is wrong, or the planet has an unexpected layering.
Precise statement
The Galileo probe found atmospheric heavy-element enrichment of roughly three times solar, while many Juno-fitting interior models require a lower $Z$ in the outer envelope, implying an inverted $Z$ gradient. Determine whether this tension arises from hydrogen-helium equation-of-state errors, deep wind effects on gravity, or a real compositional inversion. An answer is an interior model with atmospheric $Z$ that fits J_2n and $k_2$, or a demonstration that the inversion is required.
What would settle it
Interior models using independently validated equations of state and wind-corrected gravity harmonics that either remove or require the inversion.