The potential benefit is lots of electricity, which may be abundant that when amortized over the "high capital costs" could be much more cost effective than wind, solar, and storage, or may not be. We have to invest in these relatively small projects to figure that out.
Furthermore, the highly geographically concentrated energy production from fusion power could work really well for energy consumers with a similarly localized nature. I'm thinking large scale carbon capture, energy intensive materials manufacturing or processing, or large scale ocean water desalination.