I think there's a three-pronged cause for reduced trust in public institutions in the US. The first problem is that US governing elites have proven themselves

I think there's a three-pronged cause for reduced trust in public institutions in the US. The first problem is that US governing elites have proven themselves to be corrupt and untrustworthy. People in the tech sector have not been greatly exposed to this, but wages for the median person have remained stagnant for the past four decades. The elite response has been either to deny the problem or make it worse. People do notice when it gets harder to make ends meet, and the failure to address this problem has undermined faith in the elected arms of government. Other issues such as the bipartisan consensus to invade Iraq on the basis of fabricated evidence and the fact that Trump has told 20,000 lies about objective matters since assuming office have exacerbated the problem. The second problem is that conservatives--including conservative media--massively overstate the scope of governance problems in the unelected civil service as an electoral strategy. These viewpoints are amplified by Facebook and other social media in search of engagement. The third problem is low quality education among the bulk of the population. Critical thinking skills are not effectively taught, much less internalized, by the average person. Most people are not able to effectively evaluate information they are given, which leaves them vulnerable to whatever propaganda Facebook et el shovels into their feed.