Because removing ports and peripherals is a thing that Apple keeps doing.

The headphone jack was removed from iPad Pros.

Ipad pro is marketed as a mobile device.

Apple sent a survey asking once how macbook owners would feel if they removed it.

They believe the answer is going to be Bluetooth.

Music production is usually Mac at this point, and that requires wired headphones/speakers. Not sure it’s big enough of a market that Apple wouldn’t drop it anyway, but Bluetooth latencies are too high to be a substitute there.

Anyone doing pro music work will have a USB interface anyway.

But, like, people listen to music and watch videos on their laptops, and it would be absurd to force them to use bluetooth headphones for no good reason.

There are still many places (classrooms, lecture theatres, meeting rooms) where the only way to drive the projector is VGA. Not because it's good, but because it's the lowest common denominator. In these places, when using VGA, the only audio input to the speakers is usually a 3.5mm jack. Remove the 3.5mm jack, and anyone who teaches or makes business presentations won't buy it.

I receive that survey. I wouldn't go that far as them betting completely on Bluetooth. But it will be wireless.