I think everyone in here want to use cryptocurrency than physical money but the fact that cryptocurrency is not better than physical cash at all. For example if there are no internet how can you use cryptocurrency? But without internet everyone is still able to use physical money as normal. But the main reason why almosst people still prefer use physical money to cryptocurrency is cryptocurrency is not legalized worldwide so people only can use cryptocurrency in few countries with few services, it's different with physical money which can be used worldwide for every services. There are still a lot of others reason for this case but I think these reasons are enough