You probably don't even have a 6s. There are so many objectors who come on these threads who have no intention of buying an Apple, have never bought one, yet tell others not to buy one because of their "experience" with one that they actually never had. So do you really have a 6s? By the way, I do not own an iPhone, I'm impartial and just don't see why people are complaining about this issue. If it's a problem for you, don't buy the phone. Other people don't have an issue because the iPhone 7 can continue to use existing headphones with the free supplied adapter. I will make a prediction - within a few months you'll be able to buy additional adapters for a buck apiece from China, to dedicate to each set of wired accessories one owns. When my iPad charging cord got frayed at the plug and I needed a replacement, I ordered a set of ten for about $6 from China, with free shipping. So you'll soon be able to get all the cheap adapters necessary from China. Getting the iPhone 7 is a non-issue regards the non-headphone jack.
I have two retired 4s phones that I use for making videos and recording music. My wife has a 5s and I have the 6s. I also have a couple of retired i-Pods but I never use them. I also have 3 different brands of Android tablets, a chrome book, a net book, and a laptop. About the only thing I don't have is an I-pad.