I think Bitcoin will Dead BTC
If every country Government Banned Local Exchanges from Accepting Deposits.
Then, there will be no more people using Bitcoin because they might be arrested in this condition.
If there are a new cryptocurrency which is more profitable, and Government Approved Legally In the future.
I agree with your first statement but I don't like it to happen, the online users will protest and make a petition. On your second thought, its impossible because how can we trust a new coin if it is not yet well establish unlike bitcoin that already running for a long years even bitcoin is not approve by the government legally, they can't easily destroy it.
There is no doubt about the probability that bitcoin might die even the chances is too low, as of now there is so many cryptocurrencies that might be a substitude for bitcoin. But bitcoin has already does things first and because of that its demand dramatically increases, right now there is low chance that bitcoin can die, it is a perfect cryptocurrency and there no way that another cryptocurrency that surpass what bitcoin already have now.