I feel this is a very good unpopular opinion, as I think a lot of the annoyance about the fair phone not having a headphone jack is that they bill themselves as a sustainable phone maker who prides themselves as reducing waste and increasing repairability of their devices, something that dongles kinda fly in the face of from an ewaste perspective.
The same target group that they are aiming at generally likes stuff like expandable storage (so that they don't have to upgrade devices just to hold all their photos and stuff) and having a dead simple headphone jack so they can use one of the oldest standard ports in the world to use their headphones.
Since most newer phones have multiple days worth of battery life, I'm more than willing to sacrifice a few hours worth of runtime (maybe even a days worth) just to have a headphone jack. And you could say that I am in the minority of phone users, which is apparently true, however I'd argue I am pretty solidly in the target demographic for a fairphone, which I'm not getting due to the lack of a headphone jack. I instead, got a Sony Xperia 1 V (stupid name for a very nice phone) which offered a 3.5 mm, expandable storage, and decent repairability.