either way, you should have told him bitcoin survived from 2008-9 till now without being hacked the way he thinks and it will continue being OK until there is a big advancement in the quantum computers front.
And Bitcoin network is vulnerable like any other network so there is no such thing as 100% security. We all have to be aware of this.
i don't know what you two mean but i am only aware of these and i doubt we can exactly call any of them "hacks"
As we can see Bitcoin is very strong nowadays. In a way that person by person accept to use bitcoin and some buy bitcoins because of it's increasing high value. Bitcoin is very famous nowadays in many people because some of it are used by not only ordinary people but it is used by different businessman, politicians and even government employees. We can say that bitcoin is very strong because it is very concrete to the use of people. They use bitcoins to earn profits in able to sustain their everyday needs and other is to achieve their wants and not just only wants but in able to give to others and to help others. We cannot say how long bitcoin will live but it's up to those who people used. That's all. Goodluck Bitcoiners!