Aside from the "positive" explanations offered in the sibling comments, there's also a "negative" one: other AI companies that try to enter the fray will not be able to compete with Meta's open offerings. After all, why would you pay a company to undertake R&D on building their own models when you can just finetune a Llama?
Whatever Meta's motivation is they help diversify models suppliers. Which is a good thing not to be locked in. As usual reality is more complicated with many moving part. Free models may undercut small startups. But at the same time they stimulate secondary market of providers and tuners.
