9 years back Bitcoin was launched, it is very much visible that Bitcoin is secure in investors hands. Miners are doing their part of the job well, but not letting any transaction getting suspicious.
i don't think that miners will be responsible is there are transactions that are not meant to be since they are just confirming the transactions. Also if you do not know, in the first years of bitcoin a back door was found. It was fixed quickly and after that it becomes very secure. The only thing that people are seeing as a problem to bitcoin is it's volatility since there are a lot of people that are being disappointed when bitcoin dumps.