Godot community likes to have new features (that's okay, everyone loves shiny new stuff), but this engine lacks performance. Several rendering techniques aren't implemented, you possibly should to take a look for these issues and pull requests, because it's very unlikely they are going to fix them soon:
godotengine/godot#77683
godotengine/godot#76291
godotengine/godot#74642
godotengine/godot-proposals#3920
godotengine/godot#70373