> Take Japanese for an example, when you have hiragana, katakana, and kanji to express the same idea

I'm sure you know this, but for readers who aren't familiar with Japanese, it might be worth saying that hiragana, katakana and kanji aren't strictly interchangeable. Sure you can use hiragana and katakana as a fallback when you cannot or don't want to use the kanji for various reasons, but normally in every situation there's a recommended script to use in order to write correct Japanese.