An API for publicly accessible profiles and posts would definitely be possible and absolutely on the roadmap, though it’s likely a bit lower on the priority list.
The subscription-based model sounds intriguing. I was thinking of something like Twitter or X, where you can subscribe to different people, especially high-profile individuals with blue checkmarks. Those are the ones you want to see daily thoughts from to feel more connected. Also, will there be an API for your app so that it could be integrated into other apps where high-profile individuals are involved? I was thinking along those lines, but hey, you're on the right path!