> That would fall under criminal law. So even if the victims couldn't sue Uber due to the ridiculous arbitration clause, the person committing the crime could still be arrested and go through the usual criminal justice process. Is that correct?

Yep. Uber doesn't want to end up in court because they connected you with a rapist contractor. They'd end up getting sued and losing the emotional appeal to the jury, even if they hadn't been negligent in their process of connecting you with a "safe" driver by doing reasonable background checks.