I think people who dislike the headphone jack must be young and not have (good) wired headphones.
Older people (older than teenagers and young adults I mean) often have a few pairs of good headphones they got over the years, and it’s a massive waste to just throw them away and buy wireless because that’s what the trends demand. And in most cases wireless won’t sound as good, because the budget needs to go to bluetooth chips, and dacs, and batteries and all that crap, instead of just focusing on audio.

According to Wikipedia, ‘The original 1⁄4 inch (6.35 mm) version descends from as early as 1877’, and it’s been an industry standard since then.
You can use it not just for headphones but as a line out, to connect all kinds of audio devices between them. You can hook up your phone to a car audio system, an old radio (if it has input, I think most do), a guitar pedal or an amplifier, a reverb or an effects unit, etc., just with the “magic” of wires.

People like having choice, it was never about saving space in phones. I like my wired bose headphones that I’ve had for 15 years and will likely last at least 15 more. Those wireless ones are the definition of planned obsolescence.

I use the headphone jack every single day, both with my headphones and with an audio-in cable for my car.

I’d be lost without it.

Also, I’ve tried Bluetooth headsets and they’ve all died on me for various reasons. I want relatively high quality headphones, and whether they’re wired or wireless, good sound tends to cost more. But I don’t want to spend more on something that will die quickly, so it’s wired headphones for me.

I use it every day on my way to work and most nights before bed.

Nobody’s mentioning the lossy sound quality of Bluetooth compared to wired. Bluetooth relies on codecs and compression in order to stream the data fast enough to listen uninterrupted.

Wired sets are lossless; and yes, some people can hear the difference.

I have never once missed it. I’ve already switched to Bluetooth for my headphones and car. At home I cast to the hifi or Bluetooth speaker.

I got an adaptor to let me use cabled headphones when I need to and I’ve used it twice, once was to test it even worked.

The use case just doesn’t exist for me anymore.