Except AMD own ATI which is their own GPU brand. So no, they're doing that because they want to move GPUs and they'll want those GPUs to be AMD ones.
Probably not but, if so, isn't that what both computer gaming and deep learning need the most?
Around 2011, I got my feet wet in CUDA and tried to calculate quantum waveforms (using a method that is mostly matrix multiplications and FFTs). I eventually went back to doing stuff on the CPU because GPU memory was too small in the systems that I had access to (256 MB), which restricted me to one job at a time, whereas the CPU (a contemporary i7) had enough cores and memory to do 4 jobs in parallel. And I needed double precision, which the GPU could only execute at a tenth the speed of a single-precision job. Also, with the GPU, I was restricted to running jobs during the night since those systems were desktops that were also used for classes. Whenever one of my calculations ran, it would occupy the GPU completely, this rendering the graphical login unusable.
I reckon that the situation would look much more favorably for the GPU today, esp. because of the larger memory sizes and because double-precision speed has caught up. But yeah, the most common uses need only single-precision.