Yes, I'm quite confident that's what OpenAI is doing. These math proofs are just a side effect of them trying to create new data out of the blue for a better model. But that's still chasing a wild goose and hitting jackpots with 10,000 active agents, it doesn't necessarily prove RSI.
RSI is simply what you get when human involvement tends to zero. Once they set up the training loop you get RSI. I am strongly opposed to this.