Showing the same amount of content on a 4.6" screen would make it prohibitively small in most cases. You wouldn't be able to read it, so putting that much content on the screen just doesn't make sense. Resolution determines how many pixels you can display, but one pixel *is not the same size on every screen*.

As an illustrative example, let's use the monitor sitting on my desk right now. This is a 1080p resolution, ~20" monitor that I use at work. I can read and see everything perfectly fine.

Here's the a screenshot of my monitor scaled to an approximation of a 4" screen with the aspect ratio maintained:

![enter image description here][1]

I think it's pretty evident that the latter is completely unusable, even though they have precisely the same resolution. Granted, the difference in screen sizes is much larger here, but the same concept applies.

  [1]: https://i.sstatic.net/OoLQ4.png