I am not sure it is actually difference.
In the lead up to the Iraq War in 2003, there was so much discussion in the media about how Iraq had weapons of mass destruction and those saying it was made up were marginalized. In the end those doubters were right.
I think in Vietnam, there was similar misleading statements about cause belli e.g. Gulf of Tonkin Incident: https://en.wikipedia.org/wiki/Gulf_of_Tonkin_incident I think that there is often disagreement on facts.
I think with Wikipedia existing, we are actually in the gold age of grounded truth.
There is always a sizable segment of the population who doesn't really care for truth though and they will just align with their side and be angry. This happens on all sides of the political spectrum. In the past this was pushed via https://en.wikipedia.org/wiki/Yellow_journalism and is still pushed via similar outlets today.