There are many, but one strategic goal is to “poison the well” for OpenAI.
OpenAI is trying to lobby for regulations that let them monopolize AI, so they are essentially the only ones that can sell it, and instead of playing this game Facebook is seeding public research so they can keep up with closed LLMs and make better cases for themselves. Which benefits them, as then they aren’t a customer of OpenAI or Google.
Another is to attract talent themselves. AI researchers love all this.
Yet another is to set the standard. The llama architecture is THE open LLM architecture because of facebook, and you run into major problems trying to run anything else, fast. Its also fostered a lot of innovations they wouldn’t have come up themselves, which they can turn around and deploy for free.
And they have a bit of a moat because hosting llama 400B is freaking expensive, and they have a ton of GPUs to do it with.