The point is that now we're at the point of diminishing return for increasing model size, unless we find a better modeling architecture than Transformer. I think this is likely true; while all the other companies underestimated the capability of transformer (including Google itself!), OpenAI made a fairly accurate bet on the transformer based on the scaling law, put all the efforts to squeeze it until the last drop a…
A model that got to the point where it's possible for it to propose new architectures, improve optimization & efficiency.
In other words, the extremely massive model that could do this doesn't need to be available to the public. It's sole purpose should be to be used internally by a company to improve itself.
This is actually the point at which many say could lead to the singularity.