The trouble is, all of those "easy" website building services are still much harder and more customizable than Facebook. If you remember MySpace, you'll also remember that a pretty signifiant minority of pages were horrifically ugly and did super-annoying things. It seems most people are either terrible at web design or have no interest in it, even if you give them a pile of dead-easy templates. Part of the reason most of my social media use went to Facebook earlier on was that the user pages all looked reasonably nice and didn't play terrible music or blink or whatever. You could still post ugly pictures or stupid walls of text, but there's a limit to how unpleasant you can make a Facebook page. Sometimes, less customizability is better.

I don't think "customization" is necessarily a problem, even if people want to make butt-ugly sites. Part of what the web offers people is the opportunity to express themselves creatively, both in terms of design and content.

I can't complain about anyone else's lack of design skills... I once had all of the text on my website bright red Nosferatu on a black background in tables with 3d bevels and a background I swiped from a surreal art site.

But there's no reason some modern, stripped down and ultra-minimalist version of a self-hosted site service couldn't borrow from Facebook's UI design (which, all else considered about the service, obviously works for the general public) and have publishing a "page" be as simple as publishing to their Facebook feed, complete with some non-editable css.

But then that gives you none of the benefits (in my mind) to having your own site (complete control over code and content) as well as none of the benefits of Facebook (integration with your social graph and discoverability) and keeps all of the downsides of a third party host.