Money created out of thin air?

What is the worth/value of bitcoin ecosystem. Don't get me wrong there is a lot of enthusiasm around cryptocurrency protocols. Other than that what is the value being added to the society from it. I don't mean to discredit or anything like that but till now cryptocurrency is just a promise of prosperity.

If you sit back and savoir a moment then you will realize that 12.5 bitcoin is being created every 10 minutes whose value is skyrocketing at the moment. It is in the range of 25k USD for the time being. 25k USD every 10 minutes is created out of thin air doesn't it bother some people. 

Bitcoin is deflationary currency which means its value keeps rising with passage of time. All fiats are inflationary which means their value keeps plummeting. Of-course it is a good idea to buy as much bitcoin possible in exchange of your fiat. But before we jump ahead and make a conclusion we need to understand do we have enough places to spend bitcoin out in the market. The value of a currency depends on its usability. Until it does not become common mode of transaction fiat will have some value. As soon as bitcoin becomes the mode of transaction in the market there will be no need for fiat and it will loose all its value. Until then all cryptos are just a promise.