I don't remember there ever was a time were FP64 was considered a big deal for mobIle GPUs.
The article is trying to debunk a claim that was never popular to begin with.
I don't think CUDA vs OpenCL is the real issue. It's the libraries that come with them. It matters little in which language they were written, since they are closed source for the most part.
AMD's Boltzmann initiative won't solve the lack of libraries.