[drvdevd]

For me the following points come to mind reading something like this, which I think you also partly addressed:

1) Cloud hosting --> might as well use the centralized application because this is still centralized.

2) Peering your own hardware for a direct internet connection is not accessible to most people.

3) even in a p2p context, your PC or mobile device is not under your full control and especially in the US, most broadband goes through one of a small number of service providers (Comcast for example)

So I agree with you: network architecture is a major stumbling block.

On second thought, though, that still doesn't mean we shouldn't strive to create "decentralized" applications that are accessible to most average people somehow. I believe this is possible and without a huge upfront cost (besides time). They could still gain power through traction.

And as far as hosting content for others in a p2p context, I think part of the point of a scheme like that is you should never be able to know what you're hosting. It should be opaque encrypted blocks of data, right?