That’s the ideal. Apps shouldn’t concern themselves with pixels. It’s the OSs job to know the hardware the machine uses.

This leads to visible moire patterns at non-integer scalings, though

We should probably have nicer scaling algorithms that account for Moirés. Also, when you see a Moiré, that’s because you are scaling a bitmap that has periodic dithering. These should be more rare now, and a good opportunity to replace them with vector images with periodic patterns that are tuned for physical dimensions rather than pixel count.