I'd say the bigger issue was the speculative trading. Why would you use it to buy things that will depreciate in value if you think the currency itself will go up in value? Likewise, why would you buy currency if tomorrow its value can tank really hard?

The reason floating crypto isn't viable as a domestic currency is it's a taxable capital gains/loss event every transaction, and not directly useful in paying those taxes. A recordkeeping nightmare, intentionally created by the tax masters.