A page from today should do something: todo: becomes a task, cal: an event. For a diary from 2019 that would be wrong. A task from back then is not a task today, and an event from back then does not belong in your calendar.
That is why old notebooks have their own way in. Archive pages are read like any other page, word for word, with headings, #projects, @people and sketches. But no tasks, events or emails are made, and nothing waits for “Confirm”. Marked lines stay on the page, “From the archive”. If you still need one, you turn it into a task by hand.