It's not as mature as other platforms, but it's built extremely well from the base up. Unity has a huge ecosystem and tools, but it's built on a shitty/messy platform full of bugs and hacks.
If I was to make a quick & simple 2d or mobile game today, I'd go with Unity. If you want to make something that will require more effort, but work well for years, Godot is better.
I definitely recommend GDScript, especially if you are using Godot 4 / GDScript 2. The language was designed to be used in Godot to make games, and in my opinion it’s very good at that. The editor integration is great, defining export variables for the inspector, adding doc comments that show up in the built in help viewer, dragging nodes and files into your script to get their onready and preload paths, etc… It’s just really nice to use, and takes literally a day to become proficient.
Yeah, I recently looked at setting up some C# dev for Godot 4 and I found documentation scarce. Conversely, GDScript was much better catered for, even allowing for the fact that the documentation isn't all there for Godot 4 yet
If I was to make a quick & simple 2d or mobile game today, I'd go with Unity. If you want to make something that will require more effort, but work well for years, Godot is better.
UE5 is the choice for anything 3d and complex.