Because there was another "Canon outperforms Fuji wide open" comment above, I wanted to see if this guessing has substance. However, I don't have a Canon 24/1.4 L II at hand, only a Sigma 24/1.4 Art which - according to various testers - "outperforms" the Canon, at least in center sharpness. Somewhere the 4 ½ ★ rating compared to the 3 ½ in PZ must be coming from...
However, the only thing I see outperforming is: I can use the Fuji with AF and focus is spot on, not matter if it's a border or center, while I have to use the Sigma with a manual adapter and need maybe more than one shot to get the focus right. At least wide open.
Here is the 100% crop from center
and her front he right border
Ignore the "50 mm" - I can choose one FL when using an adapter or manual lens without chip and I didn't change the setting - it's only for EXIF. All pictures @ f/1.4
I don't see a huge difference between those two lenses. That is kind of a relief to me because I thought the smaller wide-angle lenses could cause more problems, but since it's designers didn't need to leave space for a mirror, they somehow managed to bring a "half-the-weight" lens to shine as good as a very good DSLR lens.
Oh, and I discovered an advantage of the focus ring clutch: No matter if the camera is powered ON or OFF, the distance remains visible on the lens.
But a lens without that clutch keeps it's focus position as well. So it's not always after a lens change lost.