For graphics, yes, but not for fonts. If you scale text linearly, it just looks bad at smaller sizes, which is why vectorized fonts come with plenty of rendering hints. Add to that subpixel rendering and a lot of other typography rules, and font rendering is suddenly pretty difficult to get right.

Try it yourself, make an image of some text in 80px, shrink it 8 times, and compare that to the same text rendered as 10px. You'll notice that the shrunken image is harder to read than the actual text.