* Ability to do first-party console ports
* 3D rendering fidelity and speed
* Asset store quality & quantity
* Robustness & stability - they both have tons of bugs but with Unity there is almost always a way around the bug, due to the decades of commercial games that paved the path before you.
For one quick example, Godot's physics engine is well-known to be poor, both in terms of performance and in terms of accuracy/stability. It has tons of bugs, tunneling, jittering, etc. Both the 2D and 3D physics engines in Godot are currently slated to be ripped out & replaced with external ones of higher quality (Box2D and Jolt). But currently, that hasn't happened, so one of the foundational parts of most games - physics - is guaranteed to be broken to some degree in a Godot game.
Replacing the 3d engine with Jolt is on the official roadmap. If it were really a drop in replacement today, that would have already shipped.
But yes, all of my personal projects are in Godot now, and I'm planning to use it for some tooling at work, just because it's UI system is nicer than Unity's as well as it having better support for re-using editor UI components in an application.