It is certainly a benefit, and it would allow a handset maker to differentiate their offering more easily than they can with just software. That said, actually

It is certainly a benefit, and it would allow a handset maker to differentiate their offering more easily than they can with just software. That said, actually building custom chips for a phone is a very high risk spend because you are in a cut throat market for "off brand" phones, you don't know the volumes you can achieve, and the upfront costs of the chip are going to be large. Trying to get the calculus right so that you make money will be quite challenging.