I've been trying to get approval from Google for the sensitive scopes to use IMAP, and they classified us as needing "CASA Tier 3 Security Assessment". It looks like it is going to be a long, tedious, opaque, and expensive process.
What are you building?
An email client for Gmail.
Interesting. I take it you've seen Notion's new product?
Are you aiming to directly compete with Notion/Superhuman?
Edit: I see you're an academic, perhaps my questions are irrelevant