Don’t get me wrong. Apple removing audio jack was the biggest facepalm in smartphone history. And you can thank it for not being able to make an upgrade without sacrificing audio jack (and SD card too :/). But USB-C is getting standardized everywhere now (laptops, smartphones, etc.). What makes USB-C earphones not worth the switch?
Why should we condense the ports into 1? This is worse, not better. In fact some Chinese phones also have an IR blaster so you can control your TV and Aircon from the phone.
As for thinness is the phone, my Sony Xperia 10iii is 5.9" and very thin. Probably the smallest phone on the market and it has a headphone jack, SD card slot, and full IP68 waterproofing. Plus 3 lense camera. No need for massive stove top lenses on the back.
It can easily fit on any phone. The jack is tiny. It’s just a lie from the manufacturers to force you to buy expensive Bluetooth headphones.
My wired in ear headphones take up WAY less space in my pocket than bog bulky Bluetooth headphones with their charging case.