When you switch CRMs, export your data from a proprietary system, or integrate with a legacy internal tool, the universal fallback is always the plain text list. Additionally, AI-driven data cleaning tools often ask for a .txt file as input because it eliminates "spreadsheet anxiety" (formulas, pivot tables, hidden sheets).
With the rise of API-first marketing platforms and real-time webhooks, you might think the .txt file is dead. It is not. Why? Because and data portability will never go away. email list txt file