Baggage – When a passenger arrives late on board a flight.

There is nothing that I know, but it is difficult to prove that it is negative. The online search, which I am sure you have already done, does not seem to find such a document.

These things depend on national and local policies. I have seen cases in which the luggage is unloaded, but not always and much less in the last 10 years. This could be because there is greater confidence in detection. A particular country may have more stringent requirements that would dictate if the flight is allowed to take off with luggage still on board.

In general, and there is no official basis for this, airlines tend to forgive things more when they are out of a passenger's control than they otherwise would be. If you lost a connection because you were late, your luggage may already be there and you often do not download it. If you leave your luggage in the baggage drop and do not show up for a flight an hour or later, there is a greater cause for concern, so it is more likely to be downloaded.