The problem with subpixel images is that there are RBG and GBR monitors. Not only that, there are horizontal and vertical variations. And there's no way to tell which one the user is using on the web. And that's not even counting all the mobile number like pentile.
It's still useful though, browsers, for instance, could use it for displaying downscaled images.
It's still useful though, browsers, for instance, could use it for displaying downscaled images.