Janet Yellen Will Consider Limiting the Use of Cryptocurrency

Yellen’s comments really don’t justify the headline. Said differently, the headline should be something like “Janet Yellen Will Consider Ways to Limit the Use of Cryptocurrency for Illegal Transactions”. I.e. stuff for which it’s already illegal to transact in dollars. At this point, she’s not coming for your Bitcoins, though unfortunately I think framing crypto as directly adjacent (or an enabling mechanism) to illicit activity is a step in that direction. But honestly this has been a criticism leveled at Bitcoin for years and nothing has changed.

They should, the markets are using this as speculative trading and preys on those that don't understand the viability of the projects and rely on ignorance to drive prices up.

Not only this, but the financial safe guards of scams and transactions are moot in all major crypto-currencies.

I believe that cryptocurrency is great, and a testament of modern engineering, but the entire financial system isn't built just for speculative trading, but to provide safety and resilience in the face of bad-faith actors or general mistakes.

Just regulate “stable” coins would be a good start.