yes

I expect them to dig up people with curved pinkies due to holding phones all day

No, I don’t think headphones will changes the skull, unless you put them on a newborn. But I do wonder how much information could be lost, given how much of it is digitalized nowadays.

Headphones are not leaving divots in anyone’s skulls

divers? was that supposed to say “divots?” Are there actually documented cases of someones skull deforming from wearing headphones enough? I have never heard of such a thing.

They would be amazed on how we were able to survive for so long with our balls full of microplastics.

I think headphones aren’t tight enough to leave divots, but cochlear implants might make them wonder.

What the title says doesn’t make sense! Divers?

Divers wearing headphones? Regardless, I suspect that after a million years there won’t be much left of the headphones.

Of archeologists don’t know it: “for religious reasons”.

1. If the civilization that discovers it is more advanced than 20th century humanity, then no. They would know their purpose.
2. If it’s not as technologically advanced, the it’s possible I suppose