They want the masses to unhesitatingly believe whatever propaganda they're fed (Politician Y says X and therefore X is true, Independent Fact Checkers Say Y is true so no further investigation is needed), but not trust whatever naughty conspiracy theories they read. That doesn't work. If you're tuned to believe whatever you read is true, you can't just suddenly shut off that impulse.
You could solve misinformation tomorrow if there was a concerted societal messaging that said something like the following: "Everything you read online, from any source, may be inaccurate. People with money and power try and manipulate you for even more money and power. Verify everything with multiple sources, consider all possibilities and peoples' motives, and use your brain."
We all know that nobody with any bit of power is ever going to say anything like that.