Honestly, I find the argument that some specifically destructive event (or even a collection of events) would be pervasive enough among all intelligent species to serve as a "Great Filter" to be completely absurd. The chances that any of the examples he listed actually resulting in full extinction (or even an endless spacefaring handicap) are only moderate at best, not assured, even if they did occur. In fact, I think it's quite reasonable to expect that a species, having undergone such a destructive event and been left not extinct, would actually be pushed into space far more efficiently. With that in mind, it's certainly completely absurd to actively hope that monumental (possibly species altering) discoveries are not made.