> Part of that strategy is ... not including those that are becoming less pervasive, such as the headphone jack.

For a phone with a mission like the Fairphone, the headphone jack will not become less pervasive. An audio standard that has existed for over 100 years will not vanish in 5, especially not without a valid alternative. On the contrary, it's a must have feature to support their mission. So this whole line of reasoning is just wrong.

> To support maximum longevity and because of the IP rating, Fairphone 4 does not feature a headphone jack

If you look at other phones with a good IP rating, they can come with a headphone jack and be fine. The Sony Xperia line has some modern examples.

> Including the headphone jack would have made the phone longer and thicker.

Given how big the phone already is, and how small phones with the headphone jack are and have been, I do not believe this. I believe that it made their job easier and changing nothing else, it would have made the phone bigger. I refuse to believe there was no alternative method to fit it in.

To note there that other vendors made the same claim, sometimes specifically for phones where there then was empty space where the headphone jack would have been. So there is a history of lies in this area, which makes this claim not trustworthy, regardless the different source. Apple lied about this with the iPhone 7, the most prominent example.