Well, I'm not the one who owns the data center(s) full of all the GPUs it would presumably take to produce a gmail's worth of tokens.
However, I take your point - OpenAI has an interest in some other party paying them a fuckton of money for those tokens and then publicly crediting OpenAI and asserting the tokens would have been worth it at ten fucktons of money. And also, of course, in having that other party take on the risk that infinity fucktons of money worth of OpenAI tokens is not enough to make a gmail.
So they would really need to believe in the strategic necessity (and feasibility) of making their own gmail to go ahead with it.