Banning one form of advertising simply raises the value of the unbanned forms. The problem with advertising is that there is so much of it. That is because it is cheap for the value that the purchaser receives. If we tax all forms of advertising, it will become more expensive, and less advertising will be purchased.
It would be better to tax it by volume (i.e. per billboard, magazine page or banner ad) than by dollar since this would encourage better targeting. However, people would likely find a way to work around the easiest ways to define advertising volume, so it really would be best to start with a tax on advertising revenue just to raise the effective price.
Think of ads like ammunition. If a bullet is 10 cents, it pays to spray and pray. But if a bullet is 10 dollars, it pays to make sure you hit your target. We have too many advertisers spraying and praying. Their ammo is too cheap.