In the short term I think many sites would die, but in the longer run we would see other forms of people trying influence other people to make them buy something or vote for something or believe in something.

I fear that we would see a huge wave of advertising in disguise and other not necessarily more transparent forms of indirect funding and influencing.

For instance, there would suddenly be a very big incentive for product companies to become media companies themselves to make the distinction between reporting, advertising and simply describing their own product go away.

I believe an advertising ban would have a very large number of unintended and undesirable consequences.