This doesn't explain shit. It tosses a bunch of graphs at you with the feeling of someone suggestively waggling their eyebrows. Some of the graphs have completely valid points. Some are of unclear relevance. Most of all, the page busily works to correlate all these in your mind while carefully not actually arguing anything. That should basically always make you thoroughly fucking suspicious - no matter what the message is.
Maybe the site is completely right about whatever its carefully-only-implied point is: that's the beauty of not really taking a clear stance at all, but just throwing information at people that is likely to allow them to extrapolate whatever you want them to. You also don't have to do pesky things like providing citations, justifying your reasoning, or even explaining what that reasoning is.
I would absolutely recommend against using this as a teaching tool. It could (generously...) be used as a reference for yourself, sure, if you can otherwise back up the implied connections in a way this site did not even try. The fact that its implied point, "wealth hoarding bad" (I assume) is a fairly good one, does not mean this is a good way of communicating it.