Not sure I understand your point. There are pros and cons to open sourcing something - should we begrudge the Obsidian team the right to make money from their software, particularly when they’ve taken steps to ensure data portability? And saying that the advanced features the Obsidian team built won’t work without Obsidian is sort of circular, isn’t it? I reckon being able to walk away with your data gets you 90% of the way there.

Nobody owes you an open source text file-based note-taking app with advanced backlinking features, etc. Perhaps you’d like to set up an open source project yourself supporting Obsidian-like advanced functionality?