How exactly? Those who say things like Bitcoin can save economies and it can take countries out of inflation or it can make people earn money and have employment opportunities, need to understand that Bitcoin is just a different form of money. I know it's volatile, but can't that be a negative point when we talk about it rescuing a country from inflation? What if a country buys Bitcoin as a reserve with whatever money it currently has and Bitcoin starts losing value? How would that make them feel?

There are always two sides to a coin, and we shouldn't make conclusions only by thinking about one side. If Bitcoin can make someone money because of its increasing price, we shouldn't forget that someone can also lose the value of their money if it loses value. Even if you don't sell at a loss, your money wouldn't have the same value, and it isn't possible for a country to keep holding until Bitcoin recovers, especially if they have all their money in Bitcoin.