I do not think this is a problem as there have probably been hundreds of medical devices approved using predicate devices and which have probably benefited society due to the faster track of class 2 devices. just because it has a lower risk rating does not mean it is simply thrown into the market without proper justification of safety and efficacy. There are still protocols which need to be done to collect this data and has to be accepted by the FDA. This lower classification can mean the difference between whether a certain project gets shut down by a company because the class 3 route may be deemed too lengthy and costly to pursue. While an extremely small percentage of devices may abuse this system or slip through the cracks, I think the predicate device exemption does more good than harm.