To me, Obsidian is a perfect example of how to get SaaS-revenue without making the user captive: All data is stored in an accessible form on the user hardware, and what you pay for is sync.
X-user kepano (who is a/the creator of Obsidian) has some nice insights on this _file over app_ philosophy.
X-user kepano (who is a/the creator of Obsidian) has some nice insights on this _file over app_ philosophy.