Both crypto and fiat own something important that couldn't be denied no matter what will happen in the people's lives. Imagine, we cannot say the exact value of crypto without the help of fiat. Crypto needs fiat at the same time fiat needs crypto to have another open source for the people needs and wants.
The combination of bitcoin and fiat money means there is a need from the community, where bitcoin users are more comfortable using bitcoin for transactions. While other people prefer to use fiat money. Both are equally needed, but the way it works is different. People have choices in payment transactions.