While cash can be useful for criminal schemes, it's old and has significant legitimate use due to legacy momentum. Cryptocurrency, on the other hand, is new and post-dates regulated payment networks that efficiently handle nearly all legitimate payments, so it suffers from similar problems to unmoderated internet forums: it actively attracts a disproportionate share of bad actors. I'm not saying that cryptocurrency should be banned for that reason, but it's an important fact to note when it's being denied.
IMHO, cryptocurrency isn't the "future of money," because there are no practical reasons for anyone to use it as money. The main reasons people actually use it are (in order): for speculation, criminal activity, or (often questionable) ideological reasons. The latter is a drop in the bucket compared to the first two.
Criminals will do bad things at scale with cryptocurrency. Ransomware existed before bitcoin, but the amounts demanded were pittances compared to what can be demanded today because the difficulty of using cash or the banking system for a transaction increases exponentially as the amounts involved increase.
It's hard to move cash, but it was harder to move gold ergo we should stop using cash because it's easy for criminals to move and use gold instead. That's the line of reasoning at play here that is espoused by this argument.
Wire transfers are also hard to reverse, but banks have security ceremonies around them to prevent misuse, and good luck to you if you want to pay a $20MM ransom with an international wire transfer. Even if you were able to find a banker who wouldn't call the FBI on you, the recipients of the transfer are exposing themselves to significant risk of capture by interacting with their local banking system and by providing you with the details of their account.
Cash being convenient for small transactions and difficult to use for large ones is a deliberate feature. The point is to strike a balance between usability and vulnerability to misuse. E.g., you have to declare when you're moving more than $10K across an international border, and it's actually hard to smuggle that much cash due to the weight and bulk. Gold is also heavy and bulky, which is an important security feature of Fort Knox (even if you break in, how are you going to abscond with tons of gold bars?).
Following that line of reasoning, a briefcase full of cash on an airplane to Colombia enabled criminal schemes that were totally impractical. Having a transnational payment network itself enables schemes. So does not having the government track and verify each and every one of your transactions.
If you wanted to make a good argument here, you'd actually focus on tradeoffs and cost-benefit for Bitcoin. Is "North Korean ransomware" an acceptable tradeoff to have Bitcoin? Idk. But the prevailing "criminals will do bad things" argument is asinine because criminals did bad stuff before Bitcoin/Cryptocurrency too, and they still mostly use fiat currency for "bad things" right now anyway. The fact that North Korea has to convert Bitcoin into dollars that ostensibly they're not allowed to have just proves the point.