"Conspiracy" assumes the government is functioning in a fundamentally honest manner.
In the 70s, the public was frankly shocked to learn about the Watergate Scandal, because they assumed America operated in a fundamentally honest manner.
After Watergate, the "conspiracy theorist" developed. Because if Watergate is true, what else is going on?
Around that time, AM radio was looking for new programming after the public's music listening transitioned to FM and we got a steady diet of extremist religious programming and Conspiracy-laden talk radio. Shortly after the Fairness Doctrine ended and things really took.off. One of the biggest TV series of the 90s was the X-files.
Anyways, if you have a conspiratorial government (e.g.China), you're not a "conspiracy theorist" to believe in conspiracy. There are very obvious conspiracies at work.
The corruption epidemic the US is now facing (post Citizens United) means we no longer assume we have a fundamentally honest government.
"Conspiracy theorist" is dead. Our government is fundamentally conspiring.
The feetdraggers will slowly, begrudgingly follow--as always.