Even at 60 megapixels, the roof below is an ugly mess, with broad streaks of yellow/blue color aliasing.
Most assertions of the “N megapixels is enough resolution” are blind to the real image quality issues that abound at lower resolution, such as color aliasing and moiré and staircasing effects on edges.
I get that for many purposes a finished image size of N=24MP is enough. But that viewpoint conflates capture resolution with output resolution. There is no reason that the two need be the same. And existing cameras already offer lower output resolution, eg “small raw” variants and various JPEG and HEIC sizes. Everyone could be happy with a 100MP capture!
Sampling-resolution image quality issues are an issue even at 60 megapixels, as shown below. Yet oversampling when done at sufficiently high resolution can banish the ugly digital stuff, such as color aliasing and moiré and staircasing effects on edges.
These image quality issues are not a concern in many images. And f/11 acts as an anti-aliasing filter. But when issues do arise, they are pretty darn ugly.
So I look forward to seeing a 100 megapixel sensor in the 35mm sensor size format, for higher total image quality and and somewhat more resolution as a bonus. The Micro Four Thirds format proves that 100 megapixels would be a bare minimum to hope to overcome these issues.
Let’s hope that a Sony A7R V will bring us at least an 80MP sensor.