I think open source advocates bring some understandable but wrong intuitions to how LLMs are being distributed.

In the world of hand-coded software, binaries are hard to work with, source is easy to work with, and compilation is cheap.

In the analogous world of LLM training, model weights are easy to work with, having training data does not let you reliably change model behavior, and "compilation" (training) is insanely expensive.

So, if your goal is agency to create tools for your own purposes, 9/10 researchers would rather work from a trained foundation model than the source data. The foundation models are of course released by companies because they cost $10s of millions to train -- but releasing them enables a thriving community of research, building adjacent frameworks, and specialized models to be created by much less powerful actors.

I've never understood the dogmatism around FOSS, but I've felt I understand the ideals. Those ideals are so much better served by releasing weights than by leaving LLMs only available through commercial APIs.