It would be just as possible if RFCs were written in HTML, like most web standards are. You probably wouldn't even need a reader at that point, but you could ea

It would be just as possible if RFCs were written in HTML, like most web standards are. You probably wouldn't even need a reader at that point, but you could easily customize the styling with CSS (even user CSS with a browser extension) or just use the reading mode of your browser.