For me:
1.Bitcoin changes financial condition of many people who don't have any source of income before joining bitcoin.
2. It give platform to investor to get high profit by investing money.
3. Many people start their business offline by earning from bitcoin.
All of the above are based on bitcoins price going up, is it still going to be a game changer when the price moves sideways for several years or even crashes?
This is the only real thing that makes it a game changer, its the only current method of online payment that is truly irreversible.