Are plane's black boxes essentially useless tool in the modern age and how to improve upon it? I am just reading the latest news on the air plane crash that happened couple days ago and it dawned on me that one too many times have I read a story on the NY Times where after black box is obtained, it provided no additional information and almost always resulted in mystery. 

MH370 of course demonstrated the failure of a tool such as the black box which has limited battery and no accessibility. Many commented at that time even my own phone can be quickly located once lost, how do they lose a component in a couple million dollar passenger plane?

Air Indonesia crash further demonstrated how due to noise, the recorded data cannot be made out exactly what happened. Yes, that is precisely the problem with a voice recorder - noise is captured as well as speech and if SNR is high enough, you don't hear the speech. You would have thought engineers in this century knew better.

Many have advocated a live video streaming device such as those for CCTV. Other have suggested float on water or a better accessed versions of modern black boxes. What is the technological infeasibility here that is preventing electrical engineers from taking a more active stance towards creating a better black box? What are some of the ways that a better black box can be made?
We have this topic well covered here, here and here (which is the granddaddy of them all).

Basically, it comes down to two issues:


Regulation: It takes a long time for innovations to be approved, especially in safety-related applications.
On long-range flights there are long stretches of no radio contact (except maybe for a satellite connection), so streaming becomes impractical due to the data volume.


Black boxes have been improved a lot since their introduction and they continue to get better. Please let the investigators find and analyze the recordings first before jumping to conclusions.