Cryptocurrencies can offer investors diversification from traditional financial assets, such as stocks and bonds. While there is a limited track record on the evolution of crypto market prices in relation to stocks or bonds, so far prices do not seem to be correlated with those of other markets. This can make them a good source of portfolio diversification. Cryptocurrency transactions usually have lower fees and faster transfer times than traditional banking transactions.
Since there are several redundant copies of the transaction database, no one can seize Bitcoins. The most anyone can do is to force the user, by other means, to send the bitcoins to someone else. This means that governments cannot freeze someone's wealth and, therefore, Bitcoin users will have complete freedom to do whatever they want with their money. Combined with the benefits of diversification and the ability to hedge against inflation, the benefits of adding cryptocurrencies or crypto stocks to your portfolio begin to accrue.
With all the advantages offered by cryptocurrencies over fiat currencies and other asset classes, it's hard to argue that using or investing in cryptocurrencies is worthless.