> Proprietary LLMs will just keep growing

Strictly speaking - we don't really know if this is true. There is no study proving AI gets smarter up to a certain point. It might keep scaling forever, or one day we might unknowingly reach the soft limit of LLM intelligence. I think assertions like the one you're making require specific evidence.

For comparison's sake, proprietary models like GPT-3 now pale in comparison to the results you get from a 7b Open Source LLM. The Open Source stuff really does move along, if not at the pace everyone would prefer.