In this day of age, it's easier than ever to fork - thanks to AI. But open source isn't open source isn't open source.

MIT license, BSD license, Apache license, GNU license, etc - the worst being "source available", whereby the license still requires you to subscribe or pay for a service.

Generally the Muse Score debacle was a problem of open source freemium software - whereby important functionality was only found in the proprietary commercial binary blob.

It's "fake it until you make it open source".