wider sensor requires longer glass or it won't have anything in focus.
For example, consider a normal lens for a 35 mm camera with a focal length of f = 50 mm. To focus a distant object (s1 ≈ ∞), the rear nodal point of the lens must be located a distance s2 = 50 mm from the image plane. To focus an object 1 m away (s1 = 1,000 mm), the lens must be moved 2.6 mm farther away from the image plane, to s2 = 52.6 mm.
How many people are going to buy a cell phone that has a 5-10 centimeter lens sticking off it so it won't fit in the pocket? No one that matters, it's not profitable.