If they want to get these things into schools it would be insane to expect the schools to also supply everyone with AirPods or some other kind of wireless headphones.

I've heard wired EarPods are great or a USB DAC is under $10. It's still easier to have the headphone jack though.

AirPods have too much latency for playing music. You want wired audio for running GarageBand or Logic Pro with a MIDI controller. They could have gone with a USB-C to audio adapter, but then you wouldn't be able to plug the MIDI controller and charge the computer.

... Only a few people make music with a Mac, but it's been an important part of its history, and Apple cares about it.

This is the answer.