See, I agree with this too. You wouldn't have to worry nearly as much about the random little things that are specific to just one device or another (IR blasters, the DAC on old LG phones, etc) if you could just plug in a second USB peripheral.
But what I'm more getting at is the other way around: that wireless headphones will already have USB-C for charging anyway. And that, particularly for larger ones (that have that port directly on the device, and not in a separate charging cradle), it really seems like a waste that more of them don't leverage that -- so that, again, you could use the headphones while you charge them.
There are still wired options, though, right? I don't really miss them, the nostalgia is not strong enough to forget how often the damn cable would catch on something and try to rip the headphones off my head. Or the cord noise. I get that people do not like having to eventually replace a battery, but high quality wireless headphones are a nice upgrade IMO.
But what I'm more getting at is the other way around: that wireless headphones will already have USB-C for charging anyway. And that, particularly for larger ones (that have that port directly on the device, and not in a separate charging cradle), it really seems like a waste that more of them don't leverage that -- so that, again, you could use the headphones while you charge them.