Bitcoin is like Noah's ark for us. The time change, technology change and also people change. From fiat to bitcoin, it will become more and more useful thing but I still believe that bitcoin will not replace fiat currency. There's a lot of things to consider before it will happen if ever.
I agree with your idea, as an add on, bitcoin as a lifeboat simply tells us that it is not permanently be in its place. It goes up and sometimes down and it will develop more and more. Its connection to others and usefulness to people will also change.It gives us opportunities such as getting new earnings and payments.
That is truly a better comparison in which we can compare Bitcoin and Cryptocurrencies to because of the fact that it really helped a lot of people currently and even before. We still cannot determine what could happen in the future but one thing is certain, Cryptocurrencies are a great help to all users who have encountered it and somehow changed their direction in life.