You're absolutely right, ALAC has been open-sourced and royalty-free since 2011. My mention of Apple prioritizing ALAC wasn’t meant to suggest it’s proprietary in the traditional sense, but rather to highlight that Apple’s ecosystem tends to emphasize their own formats, like ALAC. Thank you for pointing that out, it's an important clarification!
Right, but there's a significant difference between "they only support a proprietary format we can't do anything" and "they created and open sourced a different format and we're choosing not to offer it"
What an odd claim to make, when the very Wikipedia page they link to says:
> in late 2011 Apple made the codec available open source and royalty-free.