* The most prominent actual merchants taking crypto first or only (as opposed to a novelty 13th choice between PayPal and money-order-in-an-envelope) are in it because no conventional financial platforms will touch them (Silk Road style stuff, ransomware, etc.).
* The "irreversibility" crowd. The people who are convinced that all their profits are going out the window because of the cost of honouring refunds and chargebacks, and if only we used a payment method that didn't support them... normal people tend to classify "the system will make you whole if stolen from" as a feature, not a bug.
* The "it's independent and self-governing" crowd. These are the same people who blame their gout on the Federal Reserve and 20 years ago were buying Liberty Dollars. Money is a tool, and it makes sense to have the tool be bendable to public needs, not dogmatically hard-coded into economic rictus.
* The FOMO/HODL crowd inherently keeps cryptocurrency from developing legitimacy. What is a dollar, rouble, or yuan worth? It's how much goods and services you can get for it, and that being relatively stable and predictable allows people to build an economy around it. Until we get a critical mass of actual commerce occurring in cryptocurrency, we can't say "what is a Bitcoin worth" in the same way, and instead we have speculators tossing the value wildly up and down from day to day.