I'm really wondering what's the cognitive mechanism that allows people to just discard enormous informations like this one.
I think the analogy is even more appropriate, because the general attitude to pollution (especially Climate Metldown) seems to display that same cognitive mechanism you mention. There are the small cumulative effects, the ways in which taking any meaningful measure would uncomfortably interfere with our habits. The social fabric has just molded itself to the absurd reality, and our comfort and complicity is what makes the absurdity inspire oblivion and indifference instead of alarm and indignation. And then one day, unbreathable air, food insecurity, and nominal democracy become facts of life, and the dogma of progress (rather than progress itself) is what remains a constant.
Spooks like dirt and compromising materiel exactly because it is useful for blackmail.
When Apple was first approached about their role in PRISM they, unlike other companies, chose to outright lie stating that, "We have never heard of PRISM." along with the typical boilerplate about not allowing any government agency direct access to their servers. NSA access is presumably 'facilitated' indirect, explaining why most of all claims specifically state 'direct access' in their releases.
Other companies, for contrast, chose to offer misleading but technically honest responses. For instance Facebook said, "We do not provide any government organization with ~direct~ access to Facebook servers. When Facebook is asked for data or information about specific individuals, we carefully scrutinize any such request for compliance with all applicable laws, and provide information only to the extent required by law.".
The point of this is that what companies say, especially as it relates to their involvement in government surveillance programs is pretty much meaningless. We live in a world where their lying about participation is not illegal, but telling the truth would be. Quite a dystopic reality in many ways. As an aside this is not to say that leaks came from the government, but rather that it's extremely likely that the government could trivially obtain access to Bezos' online devices if desired. And given his position in the national economy (let alone media and space industries), I would expect such desires have long since existed even if only for 'national security', which in today's world of wide net surveillance happens to overlap with dick pics. And from there all it takes is one bad actor who gets tempted by the potential value of direct evidence showing the world's wealthiest man cheating on his wife.
[1] - https://en.wikipedia.org/wiki/PRISM_%28surveillance_program%...