I am fairly uncomfortable with the thought of "one of the most transformative platforms for education of all time" being under the direct control of private corporate interests. Whose interest lies in maximizing shareholder profits at the expense of everyone else.
Aside from imposing a royalty/licence fee on every user, having platform control indirectly enables thought control in the form of restricting easy access to the mass population. The publication of material dealing with sensitive but important topics such as religion, abortion, gay rights, racism, terrorism, prostitution, child pornography etc can be curbed simply by denying them access to the platform. We are already seeing this happen to a lesser extent with Facebook (deleted posts, banned accounts etc) and Apple store (all forms of porn).
As an analogous situation, imagine if the creation of (text)books was originally patented. The patent holder would then be able to ensure that any textbooks whose contents disagreed with him do not get published simply by denying a licence to the publisher for that book.