If somebody needs ten billion dollars in additional work and investment to make that a reality, how certain can they be?
OpenAI has 375 employees (according to Google). At 300,000 a head thats 110M per year in compensation. Let's say that their compute costs are enormous and go to 200M in expenses per year. 10B is fifty years of expenses. So if they need 10B in investment it becomes obvious that they believe that they have to change something about their business in a fundamental way. Maybe that is going to be enough, but if it is so certain it becomes hard to believe that they'd need this kind of investment.
OpenAI talks mostly about trying to help change humanity, not about winning at business. Their mission is still "advance AI safely for humanity". It's not even obvious they care about winning at business. We seem to be putting that on them.
In that sense, i'm not actually sure they care whether they beat Google or not. I mean that honestly. If they care about the stated goal, it would not matter whether they do it or Google does it. I'm not suggesting they don't want to win at all, but it doesn't seem like that is what is driving them except to the degree they need money to get somewhere?
If they really succeed at most of their mission, killing Google might be a side-effect, it might not, but it would just be collateral damage either way.
Beyond that, I don't disagree, i actually agree with you. My point on that front is basically: "Everyone thinks this will be cheap and easy very soon, and change the world very quickly".
I believe (and suspect OpenAI believes) it will be very expensive upfront, very hard to get resources in the short term, and change the world slower as a result