France as a whole is way too centralized on Paris and it's actually hurting the country. If you do read French, there is a very interesting book from 2024 (IIRC) about this. It's called "Quand le parisianisme écrase la France".

Before reading this book I always thought Germany (where I grew up) was the exception for being more decentralized. But it looks like actually France is way more centralized even compared to other pretty centralized countries.