https://www.mongodb.com/docs/manual/reference/command/update/#mongodb-data-update.n

Relevant slack thread: https://mongodb.slack.com/archives/C0UDE2DL6/p1696882572455669

The value of `n` seems to imply here that it indicates the number of documents matched. However, in the case of an upsert, `n` indicates the number of documents inserted.

We should clarify this in our docs.