We're reaching scaling limits with transformers. The number of parameters in our largest transformers, N, is now in the order of trillions, which is the most we can apply given the total number of tokens of training data available worldwide, D, also in the order of trillions, resulting in a compute budget C = 6N × D, which is in the order of D². OpenAI and Google were the first to show these transformer "scaling laws." We cannot add more compute to a given compute budget C without increasing data D to maintain the relationship. As the OP puts it, if we want to increase the number of GPUs by 2x, we must also increase the number of parameters and training tokens by 1.41x, but... we've already run out of training tokens.
We must either (1) discover new architectures with different scaling laws, and/or (2) compute new synthetic data that can contribute to learning (akin to dreams).