> if I stop paying for sync, I still have my notes and a fully functional product

The same is true for Muse. When your membership expires (or you cancel it) the app reverts to free mode, which allows you to read, copy, and export all your data. But if you're over the free card limit then you can't create new content.

That said I have total respect for the Obsidian model. They're really successful for very good reason.