you cant kill Bitcoin
it will die itself, because the cost of supporting decentralized technology is too high comparing with the alternatives
Presuming that you are talking about the current financial system then that is just incorrect. Presuming that you are talking about some other cyptocurrency that nobody uses or supports, then, good luck with that line of thinking. There is no other (current) viable solution to the Byzantine generals problem, which is the primary reason that bitcoin (or any "cryptocurrency") has got anywhere. Without that, all other flavours of crypto are useless (unless build on top of bitcoin).