That's asking too much. SaaS should give an option for you to export all your own data in a simple, parseable format (like JSON). That's about it. They don't owe anyone their source code, and they don't owe any ethically sourced data (such as employees researching and manually entering).

API access needs better terms. Like guaranteed access for X years at $Y price with Z days notice if there's a change, where Z > 3 months or so.