I don't believe this scenario to be very likely because a lot of the 'magic' in current LLMs (emphasis on 'large') is derived from the size of the training datasets and amount of compute they can throw at training and inference.
It's like a graphics designer being limited to chose between local MS Paint, and Adobe Creative Cloud. Okay, so Llama 3 8B, if it's really as good as you say, graduates to local Paint.NET. Not useless per se, but still not even in the same class.
Llama 8B is ChatGPT 3.5 (18 months before L3), running on all new iPhones released since October 2022, (19 months before L3). That includes multimodal variants (built outside Facebook).
Alternatively synthetic data might drive the next generation of models, but that's largely untested at this point.
On the same token, those of us who are sufficiently motivated can maintain and utilize a local copy of Wikipedia…frequently for training LLMs at this point, so I guess the snake has come around, and we’ve settled into a full-on ouroboros of digital media hype. ;-)