There is no use case for the headphone jack that can't be better handled by the lightening connector or bluetooth. Seriously. Want to integrate something from sparkfun? Bluetooth is what you want.
I think it's kinda funny how Apple haters / android zealots always talk about how Apple has lost its way, every time they do something new and significant.
iPod: complaints iPhone: complaints Mac Pro: complaints iPad: complaints and jokes Apple Watch: complaints. All of these have been hugely successful products.
But the day of their announcement people complained about how much they obviously sucked.