How is the internal representation an issue?
Java string are utf16 internally and it's doesn't matter how you write your code nor what's the targeted format.
It's an issue because there's nothing internal about the representation in Ada: They're regular arrays of Character/Wide_Character/Wide_Wide_Character, and string literals have different type depending on the width required to represent it as such.
Also, string representations very much matter if you're coding with even the slightest amount of mechanical sympathy.
Also, string representations very much matter if you're coding with even the slightest amount of mechanical sympathy.