And what is the image quality and do they cover the same sensor size?
Photography
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Look at Fujinon 56mm f:1.2. Which is also large.
Yet TTartisan 50mm f:1.2 is really small.
Autofocus means the lens will be larger, for example.
I'll just add there are great small modern lenses, e.g. Samyang's tiny lenses for Sony full frame. Not pictured is the 24/1.8 which is a similar size yet similar quality to the Sony GM 24/1.4, other than the aperture, though not all of them are quite to that level optically.
You are specifically looking at big heavy lenses. Auto focus also adds weight and size, especially as the elements get larger.
I have 3 Voigtlander lenses for Fuji that are the smallest SLC lenses I have seen and they are quite new.