Llama had already become a defacto standard for LLMs, between all the fine-tunes and llama.cpp. Giving it a wider license really cements it as a standard while making everybody use it on Meta's terms. It's an "open source" strategy where all the benefits accrue back to Meta instead of the community but that's permissive enough to placate most people.

Personally I feel like it's a dangerous precedent because it shifts open source from a community concept to something that a company lets you have with a bunch of conditions.