open source vs source-available. Companies taking an extremely cautious approach to AI can't use source data that is potentially a violation of copyright (pending worldwide court decisions and/or regulation on said topic). Although that cat is already out of the bag for basically every stock-traded company using LLMs trained on non-licensed data, so I don't see there being much actual risk in using them.
I wouldn't say that no one cares, but obviously many fewer people care when the cost of "recompiling" a model from its open source training pipeline is so high. Also, if you only have the weights, you can still use it to generate training data for a new model (i.e. distillation) so it's inherently less locked down then closed source binaries were.