As much as I sympathise with what you say, comments such as “the public deserves to know” or the public demands to know” or the “public think it’s nuts” are simply not true. Yes, some people genuinely have concerns over flying and accidents unfortunately bring out these (unfounded) fears but the average member of the public has already totally forgotten about this accident and goes about their normal lives.
There seems to be a ghoulish fascination about aircraft accidents when almost every man and his dog on this forum becomes an accident investigator or aircraft designer overnight dissecting every piece of miscommunication and misinformation and comes to totally unfounded conclusions based on 1 minutes Wikipedia research!
Professional pilots actually have not only a professional interest but also a need to know why an apparently serviceable aircraft in cruise with no inclement weather suddenly departed its cruise and crashed. They are in that position themselves and need to know what happened that led to the deaths of 2 of their number so that they can avoid the same fate. This is the major benefit of a forum like this. It is finding the DFDR/CVR of AF447 that has led to an increase in training in handling stalls, possibly preventing future similar accidents.
Unfortunately, bean counters and those not directly involved in aircraft operations do not see the same problem. Most times the DFDR and CVR have been found, so what does it matter? The same reason the ULB was given such a puny battery and a signalling protocol that was designed to be easy to implement rather than to aid recovery in deep sea scenarios. The cost of the last 3 or 4 under-sea searches would have equipped the world wide transoceanic fleet of aircraft with really advanced technology. But it does not come from the beancounters' budgets it comes from the tax payers of the countries involved; so 'shrug' who cares? The charges for searches for aircraft should be levied on the airline - or more specifically on its insurers. This would result almost immediately in retrofit of more suitable DFDR/CVR location systems or streaming of their data in emergency.