You are attempting to move the goalposts. There are two different points in this debate:
1) Modern LLMs are an inflection point for coding.
2) The current LLM ecosystem is unsustainable.
This submission discussion is only about #1, which #2 does not invalidate. Even if the ecosystem crashes, then open-source LLMs that leverage the same tricks Opus 4.5 does will just be used instead.
But it's only an inflection point if it's sustainable. When this comes crashing down, how many people are going to be buying $70k GPUs to run an open source model?