What major problems are crypto and btc facing in the future? One I can think of is taxes. Will there be offshore tax havens set up for people to exchange their btc, eth and other crypto into fiat without paying taxes? It's not really decentralized if you have to pay the government a cut of it.  What if you are given btc, is that still taxed?

How to spend your crypto? Will you wait until retailers accept your crypto of choice? There are options like tenx card, but what are the tax implications of using that? Even if retailers accept crypto, say monero to buy groceries or pay your rent, will you not still have to pay taxes on that?

Another problem could be power outages, internet disruption. What if there is a power outage for a year or two? What if the internet is disrupted globally?