I just want something that I can use to record notes, with good backups, and a format that doesn't lock me in. Obsidian offers that. It has a pretty decent mobile app and desktop app, in terms of the actual editing. And if I do want to do something advanced, like automatically generate a daily note for recording what I worked on today, it can do that. You can do all these things with other programs, or even just raw files, but Obsidian adds just enough to make it easy.