If only they could find malaysia flight 370.
Minerve was not under rogue command as seems highly likely of MH370, incommunicado, and thousands of miles off-course. She didn't face a terminal impact at many hundreds of miles per hour. Submarine construction is vastly more substantial than airframes, and includes far more ferrous material, leaving a magnetic and sonar signature far greater than aluminium.
What remains of MH370 are small pieces widely scattered in an unknown area with a huge degree of uncertainty, having travelled many hours some 50 times faster than Minerve.
The location difficulty is not remotely comparable.
Have you ever seed a headline that reads "Map found in attic" and the first post is "I read that as Man found in attic hah"...and you wonder what the point of even posting that was?
Obviously, this is a social media website with a fair amount of watercooler chat, not something super-rigorous like /r/AskHistorians. But downvotes are a way to filter out useful content from non-useful content. They aren't saying "you are wrong to think that way".