Thank you. I had seen that, and had browsed through it, and thought: I don't get it, the reason for this 1800 must be elsewhere.
What am I missing? Where does it show there how the claim of "1800 ELO" is arrived at?
I can see various things that might be relevant, for example, the graph where it (GPT-3.5-turbo-instruct) is shown as going from mostly winning to mostly losing when it gets to Stockfish level 3. It's hard (/impossible) to estimate the lichess or FIDE ELO of the different Stockfish levels, but Lichess' Stockfish on level 3 is miles below 1800 FIDE, and it seems to me very likely to be below lichess 1800.
I invite any FIDE 1800s and (especially) any Lichess 1800s to play Stockfish level 3 and report back. Years ago when I played a lot on Lichess I was low 2000s in rapid, and I win comfortably up till Stockfish level 6, where I can win, but also do lose sometimes. Basically I really have to start paying attention at level 6.
Level 3 seems like it must be below lichess 1800, but it's just my anecdotal feeling of the strengths. Seeing as how the article is chocabloc full of unfounded speculation and bias though, maybe we can indulge ourselves too.
So: someone please explain the 1800 thing to me? And any lichess 1800s like to play guinea pig, and play a series of games against stockfish 3, and report back to us?