We used to have earbuds that don't need to be charged because they had a headphone jack, didn't get lost so easily because they had a cord attached to a headphone jack, never lost the bluetooth connection because they had a headphone jack, and they cost less because they had a headphone jack. https://bsky.app/profile/daisyfm.bsky.social/post/3l3mfjc6sn62k
Adapters are a cop out. Just put the adapters in the phone. It also means you can't charge and listen to music.
Also while there are some natively wired usb-c headphones, I can't think of any. Any decent headphones will use a standard 3.5 or 6.5mm audio jack, and then the dac being built inwith those usb-c headphones means you can't use a seperate dac, it means you can't plug them into studio gear. It's just so incredibly limiting.
There is already a universal standard (3.5mm/6.5mm jack) it carries analog audio, why change to a digital connection which requires digital to analog conversion? Why not let the user be able to have a dedicated piece of gear to do that if they wish.
No professional equipment, or even semi professional equipment uses usb-c. It's a good old fashioned analog audio jack and it's like that for a reason