Imagine the same argument for USB-C: at some point phones will be too slim to allow for that port, should every maker start dropping it right now ? That would be nonsense.

On adapters, it's no panacea: you still want the USB port available. Split adapters exist, but most of them only allow for charging, and the charging rate is also usually miserable.

You could say people who appreciated that should just eat it and feel in their bones how much the world doesn't care about them, that would be fair. Now staying sour about it is also one's prerogative.

PS: The biggest part for me is every other devices I own still having a pretty good jack. Laptops still have it, game consoles, VR headsets, TVs, high fidelity portable players, cars etc. So keeping around a very good headphone pair is still an enjoyable thing, except for the damn phones. Even in XL sizes. They're the only one needing a dongle, and regardless of the price that sucks.

Just because people think it looks neater than the more practical alternative.

The S2 had an amazing form factor - also with a small bulge, but at the bottom. It's a thousand times nicer to hold and carry than pretty much anything that came after. The S5 was fine too (waterproof AND you could pop open the back to swap the battery, if you can believe it!)

It's silly how much more ergonomic phones feel that don't have to compensate for an extra half millimeter.

* Many phones had this, but it's getting really bad now. Older phones typically also had the lens recessed to protect it, with a slim border around it. No more space for that now.