That's mainly a limitation of the ADC / sensor combo however - and if course processor speed. Most cameras don't have the processing power of a high end smart phone.

Considering Sony also makes some of the best sensors in the world and has made FF sensors that can do 4k at full readout I don't see a reason they couldn't do this for a phone. 48 mpx sensors would potentially also scale down nicely to 12mpx (4K) for reduced moire if they do decide to skip lines or rescale in a less demanding method. I think I'm more surprised they haven't made a 33mpx sensor which would be native 8K - that would be a happy middle ground between 12mpx and 48.

I think the real interesting part of this is that the main camera is 50mpx while purportedly outputting 48mpx - this sounds like they are using the edges for stabilisation similar to how pro video cameras do (many shoot slightly higher resolution and then do a small crop to stabilise). This is one of the best forms of stabilization outside of a physical method and could be great for handheld video.

Definitely though if it can shoot full sensor readout that would be ideal - it really hurts low light performance to throw away all those pixels. The real holy grail would be if they can make a device that shoots video in something other than h264/h265 (or even 10 bit h265 at 4k). And I suppose if the phone could be used as an external recording device and monitor for a real camera (like the Atmos Ninja) to record prores or dnxhr that would be amazing as well.

Hope this isn't true. The current 12 MP setup produces one of the best video out of all Android flagships as all the pixels can be used for video recording (unlike those pixel binning sensors). This is why iPhones consistently beat Android because most Android phones can only use 25% (48 MP) or 10% (108MP) of the sensor for video recording.