Solar and wind have massive environmental impacts. Fusion's foot print is much smaller for the same output. Batteries are rather dangerous. Fusion is -- as far as I understand it -- much less likely to escape a reactor due to how difficult it is to sustain the reaction. Moreover, it's more dependable.
So in sum, the advantages are (1) dependability, (2) safety, and (3) small footprint.
My source is the fact that solar panels cause shade on the ground and squander energy that would normally be going towards developing biomass into developing energy instead. It just doesn't seem healthy for the animals and environment that live there. Especially with the talk of in ground installation, which basically destroys entire environments and soils and covers it with impermeable membranes. That's not great for soil health.
Even the great deserts of the southwest have life. In fact, I challenge you to drive through these tens of thousands of miles of landscapes in the hour or two after a rainstorm and tell me they're dead. You're missing out if you've not seen the desert in bloom.
I grew up by the desert, and I don't know why people think it's dead. There are some extremely fragile ecosystems there.
So in sum, the advantages are (1) dependability, (2) safety, and (3) small footprint.