This only works if you’re the only bookmaker in town. Even if your potential counterparties place their own subjective odds at 1:7, they won’t book action with you at 1:7 if they can get 1:5 somewhere else.
Perhaps I misread OP’s motivations, but presumably if you’re looking to make money on these kinds of forecasts, you’d just trade stocks. Sure, you can’t trade OpenAI per se, but there are lot of closely related assets and then you’re not stuck in the position of trying to collect on a bet you made with a stranger over the internet.
So, the function of offering such a “bet” is more as a signaling device about your beliefs. In which case, the signal being sent here is not really a bearish one.
It’s possible for something to be a useful shorthand even if the underlying facts are dubious (e.g., the “let them eat cake” line doesn’t come from Marie Antoinette but nonetheless illuminates the situation at the time; frogs will jump out of water if you heat it gradually but this stands in for a useful concept).
I’m not an expert-level Go player but my general sense is that Move 37 is in this same category. It was a surprising move, but it had a limited impact on the match and was not an optimal move as scored by stronger contemporary Go engines (thought it was a very good one). It didn’t shift the probability of victory, and Sedol’s move 38 was the optimal response to it as scored by Katago. It seems to have had a psychological effect because it was so surprising, but that’s possible even if a move is literally random (as famously happened with Kasparov and Deep Blue).
You can donwload Katago and work through this yourself.