My non-serious assumption is that they prioritized the classic writings of 1800s authors like Johann David Wyss in their training. These authors were paid by the word, which resulted in long pointless chapters in their books just to milk money out of the printers.

Much of the internet from the time the training data was initially collected wasn't much different. Consider how much blogspam and listicle SEO/ad optimized content would've been in the training data that is primarily interested in meandering for as long as possible to milk ad views.