??? You absolutely have the right and ability to host your own content on your own page. Facebook is incredibly popular, but it's not the "centralized" communication medium. If you want to make a political statement or whatever, you absolutely can-- presuming you can get people to actually come see what you have to say.
People use Facebook or other social media because it's significantly more convenient to do so. And distributing content on Facebook/Twitter/etc. is much more effective than trying to get people to go to your own personal website.
No doubt, but the fact file sharing networks were and still are largely self-hosted proves that people will have no issue doing the same to get a copy of some movie or music album. So self-hosting your FB-like wall or Twitter-like timeline shouldn't be much harder. If anything, I think it would be easier since the remaining data that would be stored would be relatively small (thinking of Vine-like videos, photos like you have on Instagram, etc) with the rest just being hyperlinks. Hell, I think you could make them all hyperlinks and put storage in some other distributed protocol if you have to. In any case, it's not a technical problem in my opinion, it's just a problem of making such a platform as easy as installing it on your phone without a second thought beyond are you JamesBond007SexyTimes123 or whatever you silly handle would be.
People use Facebook or other social media because it's significantly more convenient to do so. And distributing content on Facebook/Twitter/etc. is much more effective than trying to get people to go to your own personal website.