if all the governments of all the world joint hands together to banned bitcoins ,then only would bitcoin can come to an end.otherwise it is not gonna happen no where soon. because of its decentralization and no technology could beat because it is the first of its kind.
No, Bitcoin wouldn't die if governments banned it. A lot of things survive despite government bans, otherwise crimes would cease to exist altogether. This is why the illegal drug market is still thriving, and beyond that, Bitcoin's association with illegal activity would mean that the ban would just shift the market - criminals on the Dark Web would be less concerned that Bitcoin is being taken over by traders etc.
The main thing that I think could potentially kill Bitcoin is block size issues. If a solution isn't found soon and the number of transactions continue to grow, that would ironically result in disillusionment with Bitcoin, which in turn would result in a decrease in transactions from less technical users. This fall in transactions would result in mining revenues falling as there would be less transactions in each block (this would apply much more in a few years when there's another halving as transactions would be more reliant on fees) and therefore if mining was not profitable less transactions would get confirmed which would theoretically create a spiral resulting in Bitcoin's death.
That scenario is pretty unlikely and I let my brain run away a bit, but it's a shame that generally Bitcoin needs continued usage now to stay afloat, or at least will in the future.