Who decides what is misinformation? The state? The ministry of truth? That is the problem with this sort of wishful thinking.
> used to manipulate the population
The media industry manipulates opinions via TV channels and newspapers and has done so for the last 50 years. Heck, some states have their own TV channels like the BBC, France Info (France) , SVT (Sweden) which is completely ironic since the state funds them and there is no way to know how neutral these are.
> dangerous information
Dangerous information is a misnomer. You could print out how to build an atom bomb and give the step-by-step instructions for free in entire neighborhoods and no one will be able to build it because you need the right expertise and the materials to create one.
Same with bio-weapons unless you think you can develop these in your kitchen after work?
Secondly, we are back to the same problem. Who decides what is "dangerous information" and how far would you be willing to go to contain it? Censor social media? Censor private messages? What about emails? Textbooks? Listening devices in all homes? Cameras that you can't turn off in your toilet in case you pass information to someone else while taking a crap?