Because opposite is true for open source? It is actually for free, whether you contribute to it or not. Anyone can legally use it for free. Torwalds can not just wake up one day and decide to charge more.
If you feel like linux is a too much of a monopoly, you can actually fork it and compete.
But I considered that when I said "Good open weights models already exist and people can run them locally."
You can have a great LLM model with vast coding knowledge running on your computer right now, for free. It won't be the best one nor the fastest one, but still a very good one.