Re: Cryptocurrencies should be banned.
I agree on most of your statements. There are values to crypto, chiefly if transaction costs beat traditional methods, or if you find anonymity in the transaction chain has value to you.
BTC was of course first, and has it anonymity. It is an ideal tool for money laundering. Speculation on top of it is of course baloney and sooner or later it will crash and burn. BTC's major downsides are the power consumption and transaction speed are hopeless, and will eventually implode it. It is just a gamble as to when. BTC supply is ultimately, also limited by design; though fractional trading does alleviate that problem.
There are other cryptocurrencies with properties of BTC, plus other capabilities. Nano is a good example - it's got a fast transaction time, draws negligible power to transact, transactions are zero cost; and it also has anonymity. Such a thing could be incredibly useful to say, Western Union, or Visa. Or be a competitor to them, if uptake were widespread.
Fiat current is ultimately, just numbers in a table somewhere too that happens to be more or less universally accepted. Non-universally accepted currencies, funnily enough, usually tank in value.
Want to end the bitcoin insanity? Mandate that you can't trade magic beans. Job done. It might also redirect some of this stupid speculation on BTC's back into investing into, you know, actual stuff on the ground. There is a pandemic after all and the economy needs a bloody jump start.