Transporting people for money is heavily regulated in Germany on various grounds, one being safety, others are that Taxis count as public transport in germany and must fulfill certain obligations ranging from mandatory service for anyone at the same rate to transporting disabled people to the doctor (yes, that's done by Taxis as long as those people can still enter a Taxi). Uber is avoiding the regulations in an attempt to save money and be more profitable. This has been judged as an unfair business practice and so Uber faces two options: Stop offering UberPop or comply with the regulations.
The fact that private insurances don't cover commercial rides has a multitude of reasons, one of them is that statistically speaking it's more likely that a commercial driver has an accident since he's more likely to get a significantly higher mileage and more likely to drive at night. But that's a deal between the insurance company and the driver, the law only cares that you own a valid insurance, not about the exact terms.
Since it's mandatory in Germany to be insured when you drive a car, that becomes Ubers's culprit, that they chose to ignore, potentially at the cost of leaving someone without insurance coverage in case of an accident.
That is unacceptable by the German rules and that's why the decision has been made in an express decision by the court.
1) take a parcel from your home to the post office. Have an accident on the way.
2) take a parcel from your employer to the post office. Have an accident on the way.
In 1) you're probably insured. In 2) you're probably not insured.
This small amount of extra regulation covers every commercial operator.
So no, it's not a ban. It's the requirement to make business akin to getting your business registered.