Why worry initially about a disorder that only affects 5–7% of people. Fix the transportation problem for a large majority of people first, anyone else still has existing transportation as an option.
Comfort is proportional to room, there are plenty more than 7% of the population that would refuse to ride in a windowless box they can't even sit upright in.
Remember there are two passenger compartment mockups, this is the smaller one we are referring to: http://i.space.com/images/i/000/031/716/i02/hyperloop-passen...
Unscientifically I'd bet less than 25% of people would be willing to ride in that for more than 10 minutes, much less 30-40.