To claim that smartphones are a replacement for P&S cameras is I think misguided.
P&Ss perform a lot better on vacation. They don't perform as good on brief everyday interactions.
A. Action cameras- Not sure why this is a category, but people do consume GoPros like crazy [despite quality issues]
B. 4k video recording, you do have a good point there.. that's mostly for the vloging community.
C. I think this is the category that isn't well published. I just recently bought an Lumix LX10. It was expensive but the results are great.
I loved my Nikon CoolPix S6800, but Nikon decided to drop the ball and that's why I moved over. (Cannon's had a nasty red bias I couldn't tolerate)