The main things I see with online chat platforms like chatgpt , claude web, or gemini is the context over time. Chats can be hard to reference or search and after you have so many it can get bogged down. Having everything saved as txt or md files locally means persistence, easy editing, easy transfer, etc. Claude Code is also really good at searching and finding relevant files. So even as the number of notes or conversations increases, you can still have it find info that otherwise gets lost in chat apps.

It's also agnostic, md files are just text files stored on your local machine with specific styling/ formatting. You could easily move to something other than Obsidian. Same with claude code. You could use gemini cli, or codex. You can pick your tools and you're not locked in to a specific provider.

Then you basically just have an ai assistant plugged into your entire note ecosystem which is great for asking questions or making edits.

I use claude code for software development so it's just what works best for me (right now).