To illustrate this point, producing all of the electricity the United States uses in a year by D-T fusion would give around 20-100 kg of helium depending on efficiency.
17.59 MeV / (helium-4 atomic mass) = 0.117 TWh/kg
in thermal energy per kg of helium produced. The U.S. electricity production in 2019 was 4,118 TWh [1] and 4118 TWh / 0.117 (TWh/kg) = 35,196 kg.
If we assume some inefficency in the thermal->electricity conversion, I guess it should produce at least 70,000 kg/year.