It is. I saw prints of images taken with it that were 2 meter high and the amount of details was impressive. The Nikon Z 50mm 1.2 is even more resolving.

One word. Resolution. Optical Resolution.

Compare the Leica 50mm f/2 Summicron:

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https://preview.redd.it/ipa0zvm5za3c1.png?width=555&format=png&auto=webp&s=06621183bd2620dec5b9c9a20ad8ada836d1cb50

To the Nikkor Z 50mm f/1.8

78% 8 hours in.