I don’t wish for it but it would be foolish not to prepare for something like that.
Think how fragile world is now, how many ways it could go wrong, more than likely more than one thing at a time and you realize how lucky or by God’s grace we have made it so far.
If you believe in religion each has the ending of this world, even the god called science says so ice ages meteor impacts ect.
Live with no fear knowing there is a place for you in afterlife, do your duty and be a good steward of the time and resources given you. Ignoring a big potential problem is not being a good steward.