The whole world talks about unraveling its mystery?

There isn't a mystery at all because the gigantic ship drowned in water due to its faulty construction and the heavy weight. No body has done anything with that gigantic ship, and whatever happened with the travelers was their destiny. If scientists somehow gain access to the ship once again then they will know that the iceberg wasn't the real cause of its drowning, but the faulty construction and its huge weight.
The Olympic sailed for decades built with the same spec and was constructed mostly at the same time as Titanic.
It most likely would have taken ice warnings far more serious after April 1912 than before.
Were the rivets bad quality? Perhaps and this certainly wouldn't have helped during the iceberg collision.
But nothing that is on the seabed could reveal much more than what is known now.
Sonar has already "possibly" revealed the damage to the 6 water tight compartments. But this is inconclusive and could be damage due to the ship hitting the seabed as damage was found on the port side as well.
Regardless, large fragments of the hull have already been raised and analysed.
Regarding the OceanGate suicide mission; Stockton Rush was a bigger idiot than The White Star Line and Captain Smith.
The Titanic would never have sailed if the cross Atlantic line had a similar success rate as Stockton Rush's Titanic expeditions of just 15%!
If the OceanGate transcripts that have been going around are real then I'm sure Rush was panicking for the last minutes of his life as the reality of his stupidity came to fruition (offloading ballast didn't make them rise quick enough and the cracking sounds must have been terrifying).
The stupid part is that most likely the whole thing could have been avoided during a large part of the descend as they were dropping far too fast, but no one cared to even check such a simple fact for an hour.
I know that the Olympic sailed for many years even after the tragedy of Titanic, but it was successful in doing that only because the constructor The Belfast firm of Harland and Wolff, has modified it to very high extent after the Titanic was drowned in water. When that ship sank the constructor got the idea to improve their other ship so that they might not be blamed for the tragedy because if Olympic also had same fate then the whole blame would be on the shoulders of the constructing firm.
The OceanGate and its CEO was also sure that the material they have used in their submersible were not of the best quality and they did that to show the world that things can be done successfully with cheaper material than the standard expensive ones. The Stockton Rush did a deadly mission and that's why he along with some others who were in the submersible during the mission couldn't save their lives.
The communication with the mothership was also of very poor quality, but Stockton Rush had to complete this mission successfully and that's why he took the risk along with those other travelers. A lesson we can learn from those both tragedies is that never ever go for a thing which hasn't gone through proper trials, and if someone still goes for it then that person knows his fate even before it takes place in real life.