"I'd be interested in seeing what lightbulbs looked like if we designed them from scratch today"
The problem is that humans have coevolved with both sunlight and fire. While the shape of the lightbulb may be arbitrary, I think the fact that they provide uneven lighting and cast all sorts of shadows is probably necessary for good mental health. (Because it provides more sensory stimulation, and more closely mimics the natural environment as compared with what you would get from evenly distributing LEDs across the ceiling.)
The problem is that humans have coevolved with both sunlight and fire. While the shape of the lightbulb may be arbitrary, I think the fact that they provide uneven lighting and cast all sorts of shadows is probably necessary for good mental health. (Because it provides more sensory stimulation, and more closely mimics the natural environment as compared with what you would get from evenly distributing LEDs across the ceiling.)