Has non-speculative use actually grown? The ability to actually buy stuff with bitcoin looks to be on a downward trend, and the fact that the price has changed significantly over the last year feels like a negative for actual use of bitcoin.
Identity theft and ransomware are different classes of financial fraud, saying that one helps the other is like saying that petty crime helps murder; it doesn’t make much sense.
The argument is let's ban cryptocurrency that'll stop ransomware, which doesn't hold true. All you need is a fake identity or corrupt banking system to siphon off the funds you stole with your ransomware.