I'd say stronger evidence than the Othello paper is the ability to answer what-if questions coherently and plausibly.

I just asked GPT-4 "What would happen to Northern Thailand if elephants behave like kangaroos?".

The answers are probably better than what 90+% of humans could give after spending an hour researching on the internet.

The Sparks of AGI paper provides much more evidence and examples: https://arxiv.org/abs/2303.12712