Both tools are excellent for one person taking notes. The gap only shows up when a team shares the same knowledge base. Short version: Notion scales on collaboration and access control but strains on performance and lock-in; Obsidian scales on speed, ownership, and Git-friendliness but has no native multiplayer and pushes concurrency problems onto your sync layer. Which pain you'd rather manage is the real decision. I've run engineering docs on both — Notion for a ~30-person product org, Obsi...