Given you can use the same models on both, you're right about performance. However I've found the cross-session context and memory in claude code much more helpful which can lead to better outcomes faster.

Additionally helpful where 2 apps/repos might require running at the same time, e.g. headless web apps, or, for plugin development where the plugin might be a dedicated repo but needs to run in another app to observe changes and make it re-test itself.

I also switched from terminal to the app not that long ago, I don't find it buggy, it has access to a browser which is really helpful.

Just 19 too, what a talent!

Maybe it's completely intentional and it's making a comeback at least with LLMs? Google say it has no value, but LLMs probably genuinely use it.