I think it is likely the complete opposite of trouble. It helped them write their comment faster and in such a way that it was easy to understand. This is one of the best use cases for chatgpt. Rather than spend minutes trying to get the right wording, tell chatgpt what you want to say in a few short notes and get a well formed coherent text.
Now if this is a good thing, that’s up for debate - although overall I personally would say yes.
I think the point here is that for a group of people (I would argue most) the primary goal of a comment is to broadcast your ideas, with the language being used to convey them of secondary concern, of which this part could be delegated to AI.
The GPT-detector is fascinating (and seemed to work pretty well on some inputs I tested)
On the other hand, this next paragraph is scored as 84% fake and I'm quite sure Churchill didn't have Chat-GPT to help:
> We shall fight on the beaches, we shall fight on the landing grounds, we shall fight in the fields and in the streets, we shall fight in the hills; we shall never surrender, and even if, which I do not for a moment believe, this island or a large part of it were subjugated and starving, then our Empire beyond the seas, armed and guarded by the British fleet, would carry on the struggle, until, in God's good time, the new world, with all its power and might, steps forth to the rescue and the liberation of the old.
IMO, we must not be too quick to conclude that any given text was created/assisted by an LLM based on a scoring algorithm alone. (A low GPT likelihood is probably reliable [for now, until that starts being gamed].)
If you offered me even odds, I'd wager that the subject comment was 100% hand-written.
We are the hollow men
We are the stuffed men
Leaning together
Headpiece filled with straw. Alas!
Our dried voices, when
We whisper together
Are quiet and meaningless
As wind in dry grass
Or rats' feet over broken glass
In our dry cellar
Or Reddit. Let's not forget what LLMs are trained on. It's not just Wikipedia and some official text corpora, it's Reddit dumps and other regular Internet conversations. If you learned how to write English on-line, there's a chance you've internalized a style similar to how LLMs often respond.
(In fact, I often feel like I sound too much like ChatGPT myself.)