The idea of taming livestock to be used as a source of food was revoluntionary. The idea of using electricity as a source of power to fuel anything from light bulbs to give light over expensive candels, to modern day times of powering the computer you currently are using, was revolutionary. The idea of taking food and keeping it cold to make it last longer was revolutionary. Youtube is not revolutionary.
The person who invented the refridgerator was not a revolutionist. The idea to store food to keep it cool to make it last longer was long ago thought of before the fridge ever came out. All the fridge did was make this idea convenient to the masses. Before that, it was limited to a room full of ice blocks.
The idea of massive public sharing of videos, opinions, information, data, etc, etc was well in existance long before YouTube came along. YouTube simply made sharing videos easy, a convenience. Before youtube, there was/is bit torrent, before that, peer 2 peer programs, before that, user made websites, before that, Usenet, etc etc. The idea behind the Internet itself was to be able to send and share data with people all over the world.
If anything, YouTube is no more than the VCR. But unlike the VCR, you can share vidoes with people all around the world near instantaneously.Again, it's convenience. The creators of YouTube took the idea of sharing videos, and made a simple, easy way to do it. But they weren't the first ones to do it/ think up the idea.
A product is never revolutionary, it's the idea behind the product that is. YouTube is a product of the idea that there should be a way to massively share videos with people all over the world. But that idea has been around long before YouTube.