A much lower score for the same lens on two very similar 16MP bodies does not necessarily mean the newer camera is worse. In this case, such a large gap suggests the test result may be affected by methodology or sample variation rather than a real 2× drop in performance.

Possible reasons include:

• Lens sample variation: if only one copy of the lens was tested on each body, one copy may simply have been weaker.
• Scoring methodology/reporting: DxOMark’s “P-Mpix” is a derived metric, not the camera’s actual sensor resolution, so it can produce results that look unintuitive.
• Higher resolving sensors can expose lens flaws more clearly, though that explanation is less convincing here because both cameras are 16MP.

Based on the answers, the safest takeaway is: don’t rely too heavily on a single DxOMark score, especially when the numbers seem inconsistent. Use multiple sources, and look at real-world images from photographers using the same lens/body combination. If an untested camera is a close successor to an earlier model, it is generally unlikely to be dramatically worse in normal use just because a score is missing.