The Internet gives millions of people access to information they would not otherwise have had, which is a huge benefit. People who read the news, offline or online, are not inherently dupable, they like all people do not simply accept messages they are, to varying degrees, critical of what they read and not simply passive. When people spend a lot of time reading online content they can differentiate between bloggers who are untrustworthy or extremely biases from bloggers who carefully refer to legitimate sources. The problem of bad information in news-making is not unique to the Internet; there are lots of trashy magazines and poorly researched news content in traditional print channels of communication as well. We learn in formal education to double-check our sources and not believe everything we read, and we can apply that skill while surfing the Internet.
It is not enough to say that the internet contains falsehoods to dismiss the value of the internet. All mediums contain falsehoods whether intentional or unintentional but there is a much broader picture that needs to be considered in terms of the ability of the internet to provide people with freedom of expression and freedom of information, if it being a free for all has the downside of some falsehoods then thaty is a price worth paying