They could open source it and not even have a Github project associated. Just provide a read-only git repo on anthropic.com or drop a source tarball every release.
My daughter’s school had a race day to wrap up their swimming lessons, and one of the events involved rolling from front to back every second stroke. It was funny to watch but not very practical.
It’s a trend that’s a few centuries old at least. The French and Indian War was partly caused by Americans who didn’t have enough land to farm to support a family moving west, and the British trying to stop that was one cause of the Revolution, and then the whole of 19th century American history is a combination of farmers moving west because the east was full and immigration from Europe largely driven by the farmland of Europe being full. Before that almost everywhere was stuck in a Malthusian equilibrium and if you couldn’t support a family in your home, moving away would just make it harder.