LLMs write samey English that is of significantly higher quality than the median literate native speaker. There's a difference between obnoxious writing and bad writing, and when you claim LLMs can "barely speak English" you've run off the rhetorical cliff of your argument.

I agree with you contra GP that "barely speak English" wildly misrepresents LLM capabilities, but I think they don't write very well, and your characterization is also an overstatement. They often use stylistic elements that don't make sense in context: pointless metaphors, abuse of bullet points and tables when a simple paragraph would do, excessive parataxis, misplaced emphasis, dense technical prose even when unnecessary, occasionally weird word choices.

Those problems are much worse in languages other than English, by the way. I'm not a native speaker but I always interact with LLMs in English because their prose in Italian is terrible, it often reads as though the text had been written in English and then translated.

Obviously there's nothing wrong with each of those stylistic elements in abstract, exactly like there's nothing wrong with em-dashes or the word "absolutely", but I would argue that writing well means choosing styles that match the content; what LLMs appear to be doing instead is forcing the message into a default pattern, which we percieve as forced and therefore tend to dislike.

To be clear: their writing is fine. The primary goal of writing is to convey meaning, and LLMs have been perfectly adequate at that pretty much from day one. I can get over their quirks.

LLM speak is of "higher" "quality" to a superficial inspection because it uses big words in a grammatically correct way.

It is worse because it fails to communicate information well. When I say it can barely speak English, I mean that it produces sentences which are incomprehensible on the first few reads. I have never found the median literate native speaker to be so difficult to understand, partly because they use a limited vocabulary and avoid waffle.

It can barely speak English in a new and exciting way, one unlike all the previous humans who could barely speak English.

I think what the parent poster is getting at is that "LLMs don't sound natural". People don't write the same way an LLM does, which leads to a kind of 'uncanny valley' effect when reading AI text.

Over time, I suspect both human and AI writing will 'converge'. Humans are good at adopting/imitating language from a variety of sources, so I won't be surprised when we start using "load-bearing" in conversation. Simultaneously, LLMs will start sounding more natural.