People who say like that might be disappointed with bitcoin or they don't like bitcoin. Maybe according to them it's definitely bitcoin can harm people. But I personally do not respond to things like this, because I still believe in bitcoin. 
yes, there are many people who call bitcoin like that, and I think it's normal, because they don't know what bitcoin is, and how it works. well, most of them only hear bitcoin from people who are also new to bitcoin, besides they don't learn how to develop bitcoin. so it's there