Hulk The context of my question about Asian language support was removed, which makes the comment that user kyuweftea replied to unintelligable.
Also, although I don't care about the edit, I did mean to say that it does collect all the text you write, based on my assumption of how the Asian language supports works, which is based on my experience of how the GBoard is not working on GrapheneOS, which was the context removed my question.
If GBoard Japanese language support works by collecting the hiragana you type in order to offer you kanji or katakana alternatives, then it is collecting all the text you write. This would imply that it works like Google Translate--the Google Translate AI improves itself by giving you translations and also integrating corrections to its translations that users make. In GBoard, selecting a kanji you want to represent the hiragana you type in the middle of a sentence is essentially the same user process as correcting a translation that Google Translate gives you. In both cases, the system doesn't work unless Google collects what you write and its context.