Some Japanese Twitter users have noticed and are complaining (tongue in cheek faux angry Greta style) that Apple Maps no longer displays the Sea of Japan name in English or even Japanese language settings. It may be connected with recent South Korean moves to get international recognition of ‘East Sea’ instead of, or in conjunction with Sea of Japan, which failed. For reference Yahoo Japan Maps does not list any sea names, while Google Maps sticks with Sea of Japan but Google uses different place naming depending on the device region setting.
Some have suggested that Apple might be preparing to follow the Google Map naming method with updated map assets, but after months of no name, I don’t believe it. It’s just stupid Apple playing international politics. Removing a place name altogether is a boneheaded move that appeases nobody.