Apple didnt kill the 3.5 mm headphone jack, it just moved it to an adapter. Now an analyst at Barclays believes that Cupertino will drive the final nail the coffin this year the new iPhone models will not come bundled with a Lightning-to-3.5 mm adapters.
Thats not a new conclusion, in April last year Barclays suggested that this move probably wont happen in 2017 but potentially in 2018. The analysts also lowered the yearly revenue guidance for Cirrus Logic by 5%. While the components are unlabeled, the DAC chips are believed to be the work of Cirrus.
Inside the Lightning-to-3.5mm adapter (photo by iFixit)
It should have been pretty clear that the adapter was a stopgap measure a couple of years to allow consumers to move to Bluetooth headphones (or wired Lightning headphones, but who would do that?).
Apple would likely continue to sell the adapters separately (currently one goes for $9)