OP here. I mostly agree with you. If the filesystem was better at a few things then it'd be the ideal PK. Right now though it isn't enough. It's too slow or to

OP here. I mostly agree with you. If the filesystem was better at a few things then it'd be the ideal PK. Right now though it isn't enough. It's too slow or too inconvenient for most things you'd want in a PK. Creating files isn't fast or easy. Usually you need to open some other app to do it, even if it's just a terminal. Linking one file to another and showing the connection with metadata like the direction of the link is possible, but not easy, especially if you want multiple links to and from a file. You can sync with things like Dropbox, but search is painfully slow and viewing/editing files means opening a different app. It's just cumbersome. The reason I like TheBrain is actually because it's good for much more than todos and project data. I have one "file" that has over 10 thousand notes in it. It's organized arbitrarily by my preference, but definitely structured, searchable and "infinitely" expandable. The best part though is that it's really easy to visualize related data in TheBrain. In fact, as I've read comments today, I've come to realize that that is the one crucial thing most PK's are missing. There aren't good visualizations for Evernote, OneNote, most filesystems, org mode, etc. I"m with you, there's no reason the filesystem can't become the best PK, but it's far from that now.