Sure bitcoin can disappear. It's just a matter of time. But I think bitcoin wont disappear in the near future since more and more people tend to use it nowadays. Nothing last forever!
I do not understand the essence of bitcoin, if it will be regarded as fraudulent. I agree that it may be misused, but it's probably the only negative of bitcoin.
I do not think that bitcoin have negatif side. If bitcoin was used for illegal thing, it was the users fault. I thing bitcoin would not disappear becouse if bitcoin still have devootee, bitcoin will always needed. Bitcoin was helped so many people and it is very good as investment. So why bitcoin must dissapear??