I mean from my point of view you're underthinking it.

The design of page layouts for print media is incredibly precise, but that's not even the issue.

Just like think of any generic magazine. Most of the text is placed in paragraphs around illustrations and quotes and sidebars and whatnot.

Just rotating it will fuck all that up, much like when you move an image in word. (lol)

But yeah that's "overthinking" it in the sense that while that was important to an entire industry, it was basically just one industry, and everyone used/uses pdf for generic documents without a designed specific layout, and those do rotate, no problem.

Edit no wait you were 100% right I was way overthinking it. You're just basically saying you're not rotating the content on the page, but whether it's on its side on the reader or not, lol. Yeah my bad way overthought it you were absolutely right