You make some great points. But there is no way I or you can speak for what Samsung or any other Company may do for that matter when it comes to future ideations of Cell Phones, especially when profit margins are the only thing that matters. These next two years will be a defining Time For Apple and its competitors, In terms of where the Cellular World is heading.
Wireless earbuds have upsides and downsides, we will see what alternative we have with adapters when the iPhone 7 is released. In one month we should no more.
Samsung sells phones for every consumer budget in the market, so cost is a major consideration for its clients - Apple's pricing puts in the brackets of customers that it can sweat for more dollars to buy additional accessories for something that could be already done on the earlier iPhones. I am quite sure that the headphone jack will remain for the mainstream android brands - the writings are on the wall.