Admittedly I was very stuck in the 'I hate phones not having Aux' camp because I preferred wired headphones for the longest time.
I was given some fairly poor wireless headphones and was pleasantly surprised by those, so I bought a good quality set myself. Now I've gotten so used to being untethered from my phone while listening to music, or podcasts, etc that I don't think I'd go back to wired headphones while mobile.
That just leaves stereo systems, portable speakers, vehicles and the like. All of those, instead of carrying around or leaving an aux-aux cable, swap that for a usb c to aux cable.
Or even one of these:
As OP said, more space for battery. It's also one less opening to waterproof. It took me a good long while, but I've come around to agree a headphone jack just isn't worth the extra space it takes up. It's not worthless, but there's better ways to use the space.
For months, masked individuals with no police agency markings have been leaping out of unmarked vehicles that have no licence plates, refusing to identify themselves in any way, then kidnapping people off of the streets; and not one of them has faced any true resistance.
What the fucked has happened to America. Is "hey don't do that", really all you've got???