I’m inclined to think of Apple, who seem to bake accessibility deeply into their products. From my point of view, maybe their investment in accessibility has led to emergent breakthroughs in hardware design. This is just my impression however

This is absolutely true, although I'd broden it to "systems design" since software is part and parcel of the advancements. An example that comes to mind is AssistiveTouch for for Apple Watch (2021), which ultimately drove the requirement for a faster low-power Neural Engine, and which then evolved into Watch's mainstream Double Tap interaction (2023).