I don't understand what you mean? Any future fusion that requires a steam turbine to generate electricity will not be cost competitive with wind/solar/batterie

I don't understand what you mean? Any future fusion that requires a steam turbine to generate electricity will not be cost competitive with wind/solar/batteries by the time it arrives as the steam turbine will cost more to build and maintain than the alternatives even if you assume the fusion part is free. Some fusion approaches convert more directly to electricity and might make a difference, but probably not for decades.