The same reason for the small phone form factor, the 3.5mm headphone jack, and the replaceable battery disappearance. All extraordinary ideas that I would personally would like to still be a thing for the sake of providing variety and choice to all customers. There's a vocal minority that constantly asks and demands those features. But when manufacturers make and sell them, they only move a few thousand units in contrasts to the several hundred millions of sales for the traditional models. Because conceptually they might be good sensible ideas, but on a practical sense, they aren't the main priority of the vast majority.