http://wccftech.com/google-pixel-2-no-headphone-jack-explanation/

There might be a minuscule number of gripes you would find when looking at the Pixel 2 and Pixel 2 XL. One of them undoubtedly is the absence of the headphone jack. If our readers have noticed our posts, the information would continue to prattle that having the headphone jack in a smartphone is necessary because it presents convenience, but it does not appear that Google thinks in the same manner. Now, the company has also decided to explain on a support page regarding its decision to remove this important hardware component.

Google Pixel Community Manager Orrin took to a support page to explain to potential consumers as to why both the Pixel 2 and Pixel 2 XL are not shipped with a headphone jack.