You can even see it for yourself. This guy started this project 3 years ago. Fast forward to today we can see that his youtube channel has 500 subscribers and most of his videos have around 1k views...this is after 2-3 years of each video being uploaded. Basically, no one is using this site. It is no surprise that we see so many of these education type projects being half built. The developers eventually toss in the towel.
Personally I think we need a combination of both to really change education though - open educational resources and the associated tools to learn the subject better. Preferably free but also low cost might work or supported by donations.
Right now the big publishers pretty much control the entire market. They own the content and they create the tools. Then they spoon feed it to university faculty (by making tools to basically "drag and drop" the content for teachers) and the student/taxpayers ends up footing the bill for it.