Especially after the first case of somebody going sick after he enters the tube and having to remain in it the next 29 minutes. Imagine you sitting next to that person. Imagine you being that person. Imagine your kid being that person. Imagine the press ("Mother watched her kid dying for 29 minutes in Hyperloop"). Imagine the reactions. The project would be dead for good after a few such cases.
You can't put normal people in the capsules for astronauts and just think "what could possibly go wrong." Health issues and effects are real problems and have to be considered. The public is used to car traffic accidents. It won't be so for the whole new transportation suited only for astronauts. This can be the start of the grand failure.