These philosophical questions always pervade discussions of historic preservation. Individuals are free to indulge their own interests at their own expense as long as they respect and obey relevant laws and regulations. Some keep their collections to themselves, others run privately owned museums that are open to the public. To what degree do governments have a responsibility to preserve the relics of the culture they govern? Which relics are worthy of preservation at tax-payer expense? Who decides?
Personally, I find the preservation/conservation and exhibition of the Apollo 11 command capsule worthy and appropriate for inclusion in the Smithsonian NASM collection which is maintained mostly at tax-payer expense. I don't feel that way about the recently recovered engine parts. Historic preservation resources are always limited. We can't save everything. Every piece of technology associated with the Apollo program does not need to be saved and enshrined. The same is true of every WWII airplane wreck. If we try to save everything it degrades our ability to save the few relics that should be saved. But again - who decides?
I think there is such a thing as public consensus. I think public consensus is expressed through public discourse (such as this forum), museum attendance, and voluntary financial and participatory support of historical projects. The Earhart Project is an expression of a clear public consensus that Earhart's fate should be discovered.