I never said they were open source. Everything else you wrote is factually incorrect.

When you run a proprietary program (like Adobe Photoshop or a closed-source game) on your PC, you get a compiled binary of machine code. The high-level logic is stripped out, variables are obfuscated, and the EULA legally forbids you from decompiling, reverse-engineering, or modifying the binary.

With an open model, you get the actual Python/C++/CUDA code defining the exact mathematical structure of the model. And you get a weights file, which is an unencrypted, open array of floating-point numbers representing every synaptic strength in the network.

So you can inspect the exact mathematical state of the model at any arbitrary moment during inference -- in other words, you can study open models. You can fine-tune or quantize them -- in other words, you can improve them quite significantly! And much much more.