The ATH-M50xSTS StreamSet is fantastic. And it works perfectly via USB-C.
I also note that those need a large ugly USBA to USBC adapter.
If I'm honest, the design of those also doesn't personally appeal to me, and I've tried AT headphones before and I didn't find them comfortable and didn't like the sound. For phone use I'd be looking for IEMs and not over the ear models too.
I am aware that there are good USBC headphones out there, but the available options are so much fewer than analog headphones.
Also, I already have good analog headphones.
3.5mm to USB-C adapters are tiny and can include a much higher quality DAC than most phones reasonably will. Into those, you can then plug any headphone your heart or ears desire.
Audiophiles are such a niche market all things considered, and on top of that they seem to prefer their own DACs and/or headphone pre-amplifiers anyway – why waste space and money for a headphone jack that most users wouldn't use, and the ones that do would augment with external dongles anyway?
And for users that just don't want to deal with charging and pairing Bluetooth headphones, cheap headphones and adapters do just fine as well.
It’s just a worse situation all around. The DAC and amp built into the iPhone previously was of similar quality. Now life - especially working with audio gear - is more complicated and annoying, so that Tim could sell more e-waste.