Compute is the major bottleneck.

Preface: I do not consider LLaMA or any of its fine-tuned derivatives to be truly open-source, since they can't be used for commercial purposes and have highly restrictive licenses. If it weren't for the leaked weights, models like Vicuna wouldn't exist.

I think it's somewhat unlikely that a purely open-source model can catch up in the near-term without one or a combination of the following happening: a) significant funding for the compute resources required, potentially through massive donations by one or more wealthy open-source advocates, with the expectation of nothing in return since it wouldn't be proprietarily valuable b) breakthroughs in design or architecture that significantly reduce necessary compute resources for initial training and/or fine-tuning c) experts in cutting-edge AI research (the best of the best) being willing and legally allowed to contribute their unique knowledge to open-source projects, without restriction d) another company or well-funded organization intentionally and transparently releasing an in-house trained foundational model similar to LLaMA or GPT-4 to the public, along with weights, full source code, plus permissible licensing terms that allow for commercial use and further modification

I'd say the odds are slim in the near-term future, but honestly it's anyone's guess.