Perhaps the problem is SEO for persuasive writing, LinkedIn-spiration for “business” writing, and school papers for research. The machines read a lot more of this than you would. So for them human writing would appear overwhelmingly troped. Whatever works, right?
It also gets RHLFed into it by people who think the "better" sentence is the one with more puffery, and crucially it tries to cram the semantic patterns in whether appropriate or not because it's been trained to write in ways which aren't perceived as bland.
Puffery about "rich cultural heritage, a "tapestry" of sights "from the Colosseum to the Pantheon" and how they "serve as potent symbols" probably is better writing than "Rome is a city in the Lazio region of Italy with a population of 4m. It is the capital of Italy". Doesn't work quite so well when its trying to fit the pattern to the two competing diners of Bumfuck, Ohio and how the rich cultural heritage of its municipal library underscores its status as the third largest city in its county.