> (Though I would still worry. Tiny cell phone cameras are becoming better and better every year, and that's really a function of the sensors, which they buy from Sony.)

Cellphone sensors are their biggest limiting factor. Specifically, the size. Apple already seems to have squeezed as much "photo" as it can out of its sensor+image processing combination, and is using its image processing for other things (3d photos, fake bokeh).

35mm is pretty much done too in terms of large advancements in basic photo IQ. Nikon's very first full frame camera (the D3) was already 90% of the way there, and for the last 10 years they have been squeezing that last 10% out. Fujifilm isn't even competing there - they have gone for a larger sensor out of the gate.