That's what happens when a Reg author writes an article based on Android fanboy complaints about what is wrong with Apple, without thinking through whether the complaints even make sense. The only thing the DAC does in an iPhone 7 is handle output through the built in speakers. There's a DAC built in to the Lightning earbuds and one in the 3.5mm adapter, but it is hardly worth spending real money on a DAC for earbuds unless you are going to also make really high quality earbuds.
Better to let those for whom a DAC matters choose their own, since they will undoubtedly be choosing their own headphones as well.
Biting the hand that feeds IT
