The internet is arguably the ultimate expression of democracy and the free market. For the cost of internet access anyone can pull up a virtual soap box and preach to the world. There are no real gatekeepers, and the public can vote with their search entries, clicks, and links. Every point of view can be catered to and every special interest satisfied. Type in any obscure term or concept into Google and see how many hits you get (“banana farming” yielded 1,470,000 hits).
There is potentially a downside to this as well, however. Because there are websites fashioned for every opinion and perspective no one has to venture far out of their intellectual comfort zone. Virtual communities of like-minded individuals can gather and reinforce their prejudices, and to varying degrees keep out contrary opinions. This is harmless when dealing with aesthetic tastes, but can be stifling to intellectual discourse.
On the other hand defining the mission, scope, and character of a blog, website, or forum is necessary to some degree. Every site does not have to be a free-for-all. If biologists want a forum to politely discuss biological topics in a collegial fashion they have the right to create a virtual space in which to do that, and whoever owns and operates the site has the right to mandate whatever rules they wish. Allowing political activists to overrun the site and hijack the conversation would be counterproductive. Like most things a healthy balance probably works best.