We are somehow getting more immune to the scam news and now it takes quite a lot of stolen coins to have any direct impact on the price of Bitcoin. Sadly, this still happens and, if frequent, it may in the end have bigger impact, as you say. All we need, is more fundamental developments that will strengthen the adoption to convince more people to use Bitcoin. Once the trend reverses and the are more positive news, we may see the rise again. Of course, there is also a possibility of another purely speculative bubble, but that would be very negative for Bitcoin in the long run.