The problem is that what works on small LLMs does not necessarily scale to larger ones. See page 35 of [1] for example. A researcher only using the models of a few years ago (where the open models had <1B parameters) could come to a completely incorrect conclusion: that language models are incapable of generalising facts learned in one language to another.

[1] https://arxiv.org/pdf/2308.03296.pdf