I'm not saying they're wrong cause they are stating facts but they should have done some research...
I'm sure they did their research. This video is simply their way of "blogging" to give other people research material to make a decision before they go. They even stated they had military tickets at a reduced price which allowed them to not be as bothered by the state of the parks.
We can discuss if we liked their tone or not in the video - but they certainly aren't wrong in any of their points, and these are legitimate thoughts that people need to consider prior to making a decision to visit the parks. I don't think it can be stated enough - you're getting half an experience for full price.