The first point rings very true and it's not the first time this hypocrisy has been pointed out. "People should own their content, but also host on a closed-source site under a subdomain" - yes, I think you can use your own domain but IMHO owning your content without controlling the (hopefully long-living) url is kinda pointless, it's just a bit better than making a copy/paste backup of everything you post on Twitter or Facebook.