They still don't. But you seem to after how despite this, sizeable chunks of the US public nevertheless think they do?
Possibly.
- Commercialisation and trivialisation of ether media? (Well, US TV news has been crap for decades, esp. its reporting on international affairs. US public often described as wonderfully entertained by it, but abyssmally badly informed.))
- Shift of public identity from citizen to consumer? (To be entertained and pandered to.)
- Erosion of public institutions, at least partly through political agendas casting doubt on any kind of federal administration and "government" in general? (Including actual loss of competence through declining status and standards. When did the public status of US civil servants peak historically?)
- Reduction of trust between groups of the US public - "tribalization" and a return of collective rights and thinking? ("Monocultural" neighbourhoods, gated communities?)
- Erosion of the status and credibility of academic research, and science in general, in favour of politically motivated think-tank products? (Tied in with eroded trust in the government, which traditionally underpins the academic system as "disinterested" and thus assumed to simply produce "true facts", making it appear as statements on a level playing-field with "think-tank research"?)
And it's not as if all of this doesn't also plague for instance Europe and elsewhere either. Some of it might be more pronounced in the US? Ahead of a curve?