Google Apps is $60/yr ($70/yr including a domain) but is pretty much just Google Docs and Gmail.
Right now with Portal, for $96 a year you have your own secure and private place in the cloud to run stuff. A domain name, IP address, SSL certificate, SSD storage, and 4-8 VMs running apps from any developer (not just the few apps Google offers).
Medium is free but doesn't let you use your own domain name. Most blog services that do have custom domains with SSL charge more than $100 a year for this alone (and they don't run your blog in a private VM). On Portal, a blog is just another app and may require ~20% of your $8 / mo server plan.
You talk about "decentralizing" but you mention Google Apps for e-mail and Medium for a blog. If you want to decentralize, you should be running these things on your own server(s) that you control.
What am I missing?
Decentralized is for sensitive things with a need for "extra decentralized security," and that most conventional needs can be met more adequately, and cheaply, with the services 'everyone' already uses.
Basically, it's a philosophical difference, but the ideas expressed may give proponents of decentralization some insight into why we are currently in another centralizing phase of the internet.
I think those are the kinds of people you're going to want to market to. Reasonably priced for sensitive documents and files, but more than conventional app solutions who don't really need the extra decentralized security.