I am under 30, and I have interacted with music files.

edit: I don’t know about where you live, but I am definitely not the exception.

Except that many Android phones also don’t have replaceable batteries anymore.

Because Joule is the SI unit of energy, meanwhile the Watt is the SI unit of power, equivalent to one Joule per second.

“Converting” joules to watts would be like converting m/s to US dollars.

Glad I can count my own country, Lithuania, among the enlightened.

EDIT: Source of the picture: https://en.m.wikipedia.org/wiki/File:Date_format_by_country_NEW.svg