Originally posted by TaoMaas I've seen nothing convincing as to why FF is a "must".
Maybe, because not all arguments are repeated in all threads?
In a nutshell, for any given image quality there is a sweet spot, i.e. an image circle enabling best price (for camera + lens). And this sweet spot changes over time.
It is true in a mathematical sense that the sweet spot's image circle is an increasing function with time (due to different speeds of progress in silicon, optics and precision manufacturing). It's an increasing function with image quality too.
Therefore, I'm not even convinced that 35mm FF is a stable end point for the enthusiast camera segment.