> Search for 'LLM Leaderboard' and you can see for yourself. The 8b models do not even rank.

This is not true. On benchmarks, maybe, but I find the LLM Arena more accurately accounts for the subjective experience of using these things, and Llama 3.1 8B ranks relatively high, outperforming GPT-3.5 and certain iterations of 4.

Where the 8Bs do struggle is that they don't have as deep a repository of knowledge, so using them without some form of RAG won't get you as good results as using a plain larger model. But frankly I'm not convinced that RAG-free chat is the future anyway, and 8B models are extremely fast and cheap to run. Combined with good RAG they can do very well.