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.

In text? That doesn't really work. Nowadays that's become sort of a meme in video essays on YouTube, but in text you have complete control of the data rate.

Listicles and those sorts of things were pretty pointless, but they didn't beat around the bush like LLMs do. I really don't exaggerate when I say I've never seen a human write like that. Like, the moment I start reading AI responses I feel the urge to skip ahead to get to the point. I probably read at most like 10% of the words they spit out.