Blockchain isn’t something that one has to believe in. It is real and obviously being used. Believe it or not. More to your question, Who believes, those that have done the research to understand what blockchain is or those that believe in blind faith.
Will it be the future of finance? Now that is another thing all together. People in general need to understand it before it can really be used for financial uses. In some ways it is currently being used for financial reasons. Like exchanging it for fiat currency and then sending it out of the country they are in to family or businesses in another country. So in that respect it is being used as money.
Most of the world uses fiat currency (i.e.; Us Dollar, Korean Yuan, etc…). The people believe and trust enough in those forms of currency to do transactions. If they equally trusted in cryptocurrencies, they would use them as well or only them. I would prefer to use the blockchain cryptocurrencies over fiat currency any day.