Hmm. Interesting.

I've heard a lot of reasons for this trend, but that's a new one to me.

Typography is now beautiful and something to show off. There is no need for glossy UI elements or textures to hide it. If you look at iOS and early Android, everything they did was to hide the ugliness resulting from low-res screen.

Today, the content itself is beautiful.

I'm not sure that high res displays would have much to do with it. Webfonts might though.