Firebase excels for real time/multiuser/shared data scenarios. It gives you things out of the box that are not trivial to implement from the ground up. You can

Firebase excels for real time/multiuser/shared data scenarios. It gives you things out of the box that are not trivial to implement from the ground up. You can also use something like Firestore if your backend is primarily a place to store data. Combined with e.g. Next.js you can develop quite quickly with it.