The problem is that graphics cards these days are all designed for 3D Unreal engine-type games (which makes sense, given it's the more difficult problem computationally). In order to do 2D stuff correctly though you have to work backwards. In Beat Bros (Unity game) every quad is first snapped to the nearest pixel, then drawn to a low-res render texture, before it's all blown up to screen size with the point filter. Note that unless the monitor's resolution is a direct multiple of your game's, you will get slight inconsistencies between the pixel sizes. But this is hardly a problem visually on 1080p monitors, unless you are doing a very high-res pixel art game.