Comment by Pinus

I suppose one could argue that if you are ignoring things like gamma and couour space and falling back on defaults, you are not showing the image correctly. My impression is that PNG takes a more relaxed approach, and considers anything that is in the right ballpark to be correct. For example, before hi-DPI screens ("retina display" and others) most image viewers would just map one image pixel to one display pixel, completely ignoring any "physical size" values, and this was generally considered correct.