Godot 4, which is still in alpha-testing phase (currently alpha 7), does not yet have the terrain plugin and most of the other useful modules from Godot 3. However, in just a couple of weeks, the developer managed to create his own implementation of a very convincing forest .
He didn't use SDFGI (New Global Illumination Technique) as well as SSIL (Screen-Space Illumination), but limited himself to SSAO and basic shadow settings. He explained this by the fact that SDFGI is most useful for creating interiors with dynamic lighting, but even they can be shaded in other ways - without loss of performance.
And he manually wrote a handler for chunks of the terrain, procedural generation of trees on the map, and a number of other useful components for the open world game development.
And, of course, he was glad about new features: for example, automatic generation of high-quality LODs for optimization.