bitcoin is not better than fiat (in my opinion), but it can become better than fiat.
meanwhile it has many advantages:
- anonymity
- extremely low fees
- fast transactions (but slow [10-15 min] confirmations)
- ability to send very small amount (e.g. 0.0001BTC) or very huge amount (100000BTC)
- ability to send money to anywhere in the world fastest way possible.
- no need for banks
- ....