Your argument seems to mix a few arguments like: OpenAI has so much demand and it has made so much compute that it is a bad thing (?!). It can't go on (why?) hence the capabilities are stalling (how?).
Then you also say that it is too competitive which is a totally different argument to compute.
So in this thread we have multiple vectors of arguments like
- high competition
- high demand for compute (not sure how this hurts OpenAI but whatever)
- capability has stalled