That website is firmly optimised for large screens, certainly not phones. It’s not even a little bit responsive. And it still manages to have too long line-lengths (though I do like it’s hierarchy and use of white space).
The information density (text/meaningful graphics per square inch) is very low - most of the space is unused, the text is large etc. I assumed that, on smaller screens, the page would be laid out so that there's less wasted space...
