> But someone complained that they didn't like having something that wasn't tied to USD.
No, you're misrepresenting long_time_gone's point. EUR, for example, is very stable without being tied to USD, and EUR/USD will almost never fluctuate by 10% within a single day. Fiat currencies tend to be very stable even when not tied to USD.
Non-tied cryptocurrencies are extremely volatile to pretty much all fiat currencies (and to most other non-tied cryptocurrencies), while most fiat currencies are comparatively stable to most other fiat currencies, without being tied to them.