For every other type of game, I would at least check out Godot 4 once it's had a stable 4.0 release. It's easy to learn, supports .NET, and it's actually not hard at all to modify and extend if you know C++. It even compiles from scratch relatively quickly.
Unity's biggest advantage is the Asset Store. If you want a bunch of third-party plugins to make your life easier, Godot has a long way to go.
I agree that Unity has a head start, but we're betting on Godot catching up, especially for indie developers. We're doing our part by helping to plug some of the holes in the Godot ecosystem by releasing assets, game templates, and plugins.