You're not supposed to be able to read the majority of the text. That's the point, analogous to the majority of the population which doesn't have access to broadband. It's supposed to feel frustrating and exclusionary.
As nice as the concept sounds, they probably should have pointed it out. It's too subtle, seeing as most of us missed it. Even something like "You think this is hard to read? Imagine being..." would make it work better.
Making your entire message a pain to read seems like a bad idea, either way.
I sat there expecting a background image to load but ended up closing the tab, assuming the page was broken.
