If anyone is interested in summarized live updates of the hearings see:
Public hearings are 100% standard at NTSB. The point is to conduct as much of the people-side of the investigation out in public view as possible. And to have the technical experts explain their results in public too. It can be a bit of a show trial, but the idea is good.
Although I like your counterfactual of asking the general lay public to provide their pet theories for what happened. Maybe they could do some kind of crowdsourced survey and publish the top 10 most popular ideas. 
Like
They were spraying chemtrails too close to Area 51 and so the aliens kept there flew their saucer out to perform anal probing of the crew who got so distracted from flying that they lost control of the jet. Oops. But they died happy.
All that would determine is that the aircraft should have been named Crashy McCrashface.
NPR’s key takeaways from the hearings:
For my part, I am particularly unsurprised by this:
The Army helicopter’s altimeter may have been wrong — and that wasn’t unusual
Although that is specifically referring to the barometric altimeter, and it’s not clear (to me, anyway) why the helicopter’s flight crew would have been relying on the barometric altimeter at all at that altitude and with the need for such precise navigation around the airport.
And I think comments like this:
“You just told me, I believe, all of the equipment in this manufacturing process is within the tolerances for safety. How much is that tolerance?” Inman asked. “I think it should be zero.”
Are evince a serious misunderstanding of how engineering works.
Because at the end of the day, I don’t see this as being a problem with an altimeter, I see this as a problem with how the FAA utterly failed to ensure that helicopter flight paths would be safely clear of commercial flight paths going into Reagan. When a known (and eminently tolerable) instrument error contributes to a collision, you don’t blame the engineering, you blame whoever planned the flight routes without taking instrument error into account.
Anyone who tells you they’ve got a piece of equipment that works with 100% accuracy and 100% precision 100% of the time isn’t an engineer, they’re a snake oil salesman.
Devlin-MacGregor’s heart drug Provasic (in the movie The Fugitive) was fantastically effective with absolutely no side effects.*
*the loud, annoying laughter theater patrons heard following that line was from physicians in the audience.
I’m not entirely sure that this is related to the OP but the GAO is telling Congress that there’s an emergency situation with the number of meteorologists employed to keep all the planes flying, safely:
https://www.gao.gov/assets/gao-25-108597.pdf
Looking at their map, I might avoid flying in/out of San Francisco, if it’s not an emergency.
SFO is prone to fog but not otherwise dynamic hard to predict conditions.