Joke of the day! Nor Bitcoin neither Blockchain going to disappear as blockchain is here to stay and Bitcoin is a future currency that will flourish for sure.
The OP is not claiming that Bitcoin and Blockchain will cease to exist. Read the thread carefully and you will know that he is speaking about a scenario in which most of the Bitcoiners will stop using cryptocurrency under government pressure. We can't discount this possibility, as I am seeing this right now before my own eyes here in India.