I'm a big fan of responsive design, but I definitely agree about homogenization. The Twitter/Twiterrific/Tweetbot example is pretty damning, and in my opinion Eli's "dimensional" Apple Watch mockup is clearly the better design.

I think this is just a temporary overcorrection though, and that good designers will learn to find a balance. If you look at the work of someone like Ben Cline, you can already see how flat and textured elements can work together beautifully.