We used to have earbuds that don't need to be charged because they had a headphone jack, didn't get lost so easily because they had a cord attached to a headphone jack, never lost the bluetooth connection because they had a headphone jack, and they cost less because they had a headphone jack. https://bsky.app/profile/daisyfm.bsky.social/post/3l3mfjc6sn62k
Waterproofing is very difficult with a headphone jack. You'll notice virtually every single phone with a headphone jack is 'splash resistant' while many without are able to survive being submerged. It also saves a relatively large amount of internal space, for something that easy to move external with an adapter.
If we're talking about adding back in older communication standards, I would personally prefer an am/fm receiver and IR blaster; it would be cool to use my phone like a universal remote.
Something I have heard in the past but is a headphone jack that much harder to waterproof vs a USB-C port? I'm genuinely curious because I don't know. It feels like the two would be of a similar difficulty.
I think most USB-C ports have sensors that allow them to turn off when wet. I'm not sure what the challenges are doing something like that with the headphone jack.
They don't even need to do that. Just blast music straight into the water. It's not like anyone would be listening anyway.