In fairness, that's probably more due to the novelty of the disaster, more so than whoever was actually on board.

A refugee boat sinking is a tragedy, but it's also not novel in the eyes of the media (and might be difficult to report on, depending on local laws). It happens with enough regularity that it's considered another tragedy, in much the same way that America doesn't report all their mass shootings (they tend to have one for almost every day of the year), or how the local paper usually doesn't report every robbery and homicide.

The submarine incident is a bit more like a plane crash by comparison, which is rare and novel enough that it's worth reporting on, irrespective of whoever is on board. Particularly with the other facts being dug up, which only added fuel to the fire.