I see what you mean, but this is an enormously difficult lens range to build and please everyone. I think 24mm is wide enough, and a few extra mm at the wide end is a big task that would result in other compromises.
Distortion, focus speed, CA, focus shift, size, weight, across frame sharpness at all focal lengths, filter size, min focus distance,vignetting, flare control, price, bokeh are all factors. This lens truly has to be a master of so many things. IF Tokina got 90% of the above done dependably well who cares about a bigger range than 24-70mm?
F2.0 would undoubtedly be bigger, do you want that?
Just say’in
Started out doing photography at the age of 6 using an uncle's old 1940 kodak brownie box camera. At 15 years of age, I decided to buy my very own 1975 Praktica SLR camera. I now shoot with a Nikon D850. I do unpaid TFP and commercial paid work.