Maybe they would have continued to make the attempt. But unless it got snagged, the ballasts were designed to break off after 24 hours and rise to the surface.
Even a hopeless situation, people still want to see, and possibly recover, the surviving wreckage. The whole point of the original exploration was to view the Titanic wreckage. Various military spent enormous resources looking for MH370 for months/years.
And nobody with any shred of PR training would make a "heard a big boom, they're probably fucked" statement with all the world's media and the families listening. Nobody wants to tell the families that its over until they've got hard proof.
Don't quite know what was so great about this story. It was a textbook example of the catastrophic consequences of hubris meeting ignorance, and that was about it. The rest was just milking the drama as timed passed by with decreasing theoretical oxygen reserves.
> catastrophic consequences of hubris meeting ignorance
Icarus calling. People have been telling this story for thousands of years.