Cryptocurrency can obviously work, but bitcoin is not realistically going to be widely useful.

For the last three months it has had a throughput of 195 bytes per second.

https://bitinfocharts.com/comparison/size-btc.html#3m

There is no universe where the fact that everyone in the world will get about three transactions on the main chain for their entire life will give people the dream of sending money to each other directly electronically. If you start using apps and side chains for everything you are back to centralization and aren't much better off than venmo.

This is why during heavy use single transactions cost more than the hard drive space needed to store the entire chain. It just doesn't make sense to think the entire world can run on 700KB every 10 minutes. Every other decentralized cryptocurrency is more viable.