I've recently made the switch from Django/Flask to Rails. And I have a feeling that those frameworks surpassed rails in terms of maturity. Rails feels a bit hacky in comparison (ORM, migration management, validation and data management, etc)

This might be a personal opinion, and just a disagreement on philosophical cornerstones. However, if asked, I would point to Django as a starting point to whoever asks me "What should I use to start project X"