There are many valid HTML 4.01 Strict pages that are unreadable.
For instance if you use white text with a white background while it may be a valid HTML document, it's not particularly useful for being able to read the information contained.
Indeed, you are right that presentation and styles can be a problem. That said, the three browsers I used - FF/Mac, Safari/Mac, and ELinks/FreeBSD have no issues rendering it. Nor is the the stylesheet necessary as the page is readable with a disabled stylesheet on Safari/Mac and FF/Mac.
In the larger sense, a comment that a given page doesn't work for a given platform is about as useful as my pointing out that it does work for my platform.
I disagree a report like doesn't work on platform is highly useful to developers who care, especially when it's so painfully obvious as to what the issue is when loading on iOS/safari.
The reason it's not useful to you is because you didn't repro the issue but rather loaded it on a bunch of other browsers, so understandably you don't see how painfully obvious the problem is.
It doesn't really work fine in FF either; if you reduce the window size, and you want to side-scroll to read the fixed width parts, it'll scroll "over" the content, just like on iOS Safari.
Working fine only on large screens is not working fine, even for the HTML4-era standards.
