I’m sorry what? The 3.5mm is better because it’s rotational symmetrical?

Thats a minor win. You rarely really need that rotation capability, and what little you need can be made up with thinner cables (which is easier with a digital signal and DACs in the headphone, which can’t be done compatibly with 3.5mm and people are dumb) The you also have to sacrifice connection friction to gain rotation, and that has tradeoffs, especially when that friction is caused by a spring-loaded conductor (which also means more friction likely means fewer insertion cycles before friction starts dropping off).

It also really sucks at strain relief without massive dookie springs or rubber butts…and the bigger the strain relief, the more subjective it is to perpendicular force, which is really easy to do on a 3.5mm diameter cylinder of gold-plated iron/tin alloy with the fulcrum also being at the base of the cylinder.

Other cool thing about what could be done with USB-C headphones. A lot of companies put lead weights full-sized headphones for balance or comfort (more weight makes it feel more secure). Good Modern drivers don’t need to be as heavy as they used to be. How bout instead of weights, they use lipos? Now your headphones can charge your phone (when in wired mode, hell, I’m talking about fictional mid/high-end cans, they could have Bluetooth and ANC while we’re at it since they have power), and your charger port point is essentially moot.