I don't get too excited about fast lenses (< 1.4) and Nocts and here's why.
1. They don't resolve very well wide open - even the best ones.
2. Modern digital ISO can address low light situations better than a fast lens
3. Size, weight, and cost (and this is from someone that owns all 3 Otii)
4. Depth of field nonsense - play around with DOF calculator and you'll see - studio and field work will even drive this point home further. Lastly, razor thin DOF is unnatural to the depth we typically see.
5. Poor transitions into OOF.
6. LOCA and SLOCA when wide open and typically for the next 3-4 full stops.
Each one of these is reason enough but in reality, all of them occur at the same time when trying to use an ultra fast lens wide open or within a few stops of WO.
There is a joy in holding a Zeiss 1.2 or Leica 0.95 in your hand and looking through the barrel of the lens but all of that ends with the frustration of trying to get any decent photos out of these lenses. At the end of the day, it's just for bragging rights. Most sports cars capable of going 200mph have average speeds of 25mph over the life of the car. Just like a Prius.