https://www.theverge.com/2018/9/12/17827970/no-more-free-iphone-dongles

Apple included a spare dongle in the boxes of the iPhone X, 8, 8 Plus, 7, and 7 Plus phones, but it isn’t so generous this year when it comes to including a 3.5mm audio dongle in the box. The 3.5mm dongle is no longer a free accessory and the new iPhones won’t ship with Apple’s own fast Lightning to 3.5mm audio jack adapter. This includes the iPhone XS, XS Max, XR, and the iPhone 8, which used to include the free dongle.

Instead, Apple will still sell you the dongle separately for $9. Despite it being the least expensive dongle that Apple sells, it still comes at a cost now.