It's
this sort of stultifyingly ignorant and scientifically-illiterate nonsense which makes this the threat that just keeps on giving....
It's palpably ridiculous to propose - as Vixen appears to be doing here - that the Atlantic Ocean is "much deeper by a country mile" than the Baltic Sea. I'd hope the sheer wrongness of such a statement would be immediately apparent.
And for the record, TWA800 sank to around 36m. The Estonia sank to around 90m. The difference - wrt the relative ease of exploration and recovery - is actually huge. For example, someone with my scuba certification could have dived to TWA800 three times per day, and would be able to spend an average time of around 20-25 mins per dive at the wreck site. By contrast, the Estonia could only be reached by either a tech diver, high-pressure manned submersible, or ROV*. In the first of those possibilities (the only one where humans could actually touch the wreck with their (gloved) hands) the divers would only have been able to spend around 15 mins at the wreck site, and would only be able to dive once per day.
** And NB to Vixen (or
nota bene 
), "ROV" stands for "Remotely Operate Vehicle". It does not,
ceteris paribus, stand for anything else. Kimo sabi?