Not a ML expert but I think “can’t” is a strong word. There was a podcast with Mark Zuckerberg where I interpret his remarks as, Meta doesn’t want to directly complete with OpenAI, their existing AI services like recommendation already consume a lot of resources. Ads has and will continue to be a cash cow and LLMs has not generated large revenue yet. OpenAI generated about 2B revenue in 2023 (I’m sure it’ll grow significantly in 2024). Meta has made 40B net income in 2023 so you can see financially, there’s no reason to compete (yet).
Supporting your argument, Meta is competing with OpenAI, but specifically in market position. They placed “Ask AI” prominently across their platforms (for me, at least).
Meta knows where to compete, where to keep a foot in the door, and where to be a bystander.
Have you tried meta.ai which they offer for free? It’s already very competitive in terms of its abilities, they just don’t care about it or advertise it as much yet.
It's not unlikely that the Llama 3 405B that's still training will outperform the best OpenAI model of today.
The Llama 3 70B model in English already beats all models from Google, from Anthropic and it's only bested by the last GPT4 version. (Based on the Open LLM Arena results)
LLAMA 3 is pretty sweet and some of their vision stuff like segment anything is cutting edge. Facebook just don’t need to publish or make demos since they have a robust path to revenue.