It seems pretty clear what you were implying. I don't see a problem with their journalism.
This $100B is a marginal cost on top of what has already been spent, and does not include the cost to operate the system. It seems unreasonable to imply that the cost of the highways which actually connect the entire state, somehow dwarfs the cost of this project -- that's just not true. It's even more unreasonable to to imply that the journalism is flawed because it does not make that argument.