I feel that this may be similar to discovering the Titanic. It was only many years later that the technology evolved and the discovery was made. We will have to wait, and not give up.
It really depends on how many people still CARE by then. As I said, the Waratah was lost before the Titanic, but the public was obsessed with the Titanic I guess because of the Europe/New York visibility. Look at all the movies that were made between 1912 and 1985.
More to the point, there is a list somewhere on Wiki of all the passenger aircraft that disappeared without a trace that no one ever found to this day.
I hate to keep sounding like a pessimist, but at least with the Titanic, we had a reasonable idea WHERE she sank. We don't seem to in the case of MH370.
But in a part, I agree with you about technology. Who knows- in the next 100 years, it may be possible to scan the surface of the oceans in detail from satellites in space.
Gonna have to be FINE detail if she came down in pieces like TWA 800.