If Bitcoin was not invented, probably people will still look for other ways to invest their hard earned money and gain a big return of investment. People will still search for ways to earn online and have a secondary source of income. They'll still engage or they will engage more with the stock market and forex exchange. It's not that of a big loss, but it is a loss of an opportunity to 'gain more' if Bitcoin is not invented. Bitcoin miners aren't the only on affected here if ever it was BTC is non existing (since you only mentioned the miners) traders an investors are or will be affected bigtime as well. But anyways... it is really great that Bitcoin was invented and founded by Satoshi Nakamoto and it became popular (and is becoming more and more popular) and successful.