The share sheet lets us integrate with various apps or shortcuts.
For example, I often want to translate some sentences in the document to my native language.
However, right now, I have to copy the sentence, close GoodNotes, open Safari, paste it to some translation website (e.g., DeepL), and then go back to GoodNotes, which is kind of annoying.
If there were a share sheet, I could simply select the sentence, tap on the "Share" button, and choose whatever shortcuts I want to use.