@1000000
The big message here is more about the scale of energy needs and less about how we achieve it. We could jump from type 2 to type 6 depending on how our tech tree unfolds, and no one really knows how the tech will develop. Type 2 may not even be in the tech tree, we could develop fusion reactors on Earth that feed us more than enough energy until our tech tree develops some strange dark energy reactor that surpasses type 6.