It's also all a design, and you'd be a fool to believe any upfront cost-projections are going to be hit.
ITER was not as expensive as it is back when it was designed either, but building things which have never been built before is full of risk.
In a sane world, we'd be funding both and probably more, seeing as how fusion power is basically one of the single most important technologies we could perfect in the modern age.
True, but we have built working tokamaks like JET, which is about the same size as MIT's design, so it's not like the numbers come out of thin air either.
ITER was not as expensive as it is back when it was designed either, but building things which have never been built before is full of risk.
In a sane world, we'd be funding both and probably more, seeing as how fusion power is basically one of the single most important technologies we could perfect in the modern age.