To be fair there was no one tracking the migrant boat because they were crossing illegally. We knew the sub went missing basically as soon as it did rather than when people started spotting bodies. In situations where migrant boats are found before/in the midst of sinking help is sent (although after that it’s probably a trip to the detention centre.)

The Greek shipwreck is an unfortunately common tragedy. Whether in the Mediterranean or elsewhere migrant bodies frequently wash ashore. The Titanic story is something novel, and I think at least partially people see it as something justified for adventure tourism exclusive to the extremely wealthy to end poorly. There is nothing to really get excitement out of from the shipwreck, it’s just sad.