This is one more reason why my next phone may not be an iPhone. I can use USB-C audio on my laptop (plus 3.5mm of course). If I could use it on my phone, and on the iPad, then problem is solved.
If I stick with Apple, I'd need 3.5mm analog headphones plus two adapters - one Lightning for the iPhone and one USB-C for the iPad. One was messy but, ok, whatevs. Two is just dumb.
Guess what Apple - I'll switch to a different phone and I can stick to just USB-C headphones, and won't have to try to juggle multiple adapters.
I don’t think I’d switch my entire digital life over a port.
Regardless, even if Apple adds a USB-C port to the iPhone (which I doubt), doesn’t mean your usb-C headphones will be compatible with it, or with your Mac and iPhone, or iPad. Apple doesn’t even make USB-C headphones.
https://www.soundguys.com/usb-audio-explained-18563/