Another thing cryptocurrency people get wrong: Referring to an eventual fixed supply (e.g. 21M BTC) as "deflationary" and an eventual unlimited supply as "inflationary".
In reality, deflation means demand is increasing faster than supply and inflation means supply is increasing faster than demand. A cryptocurrency with open-loop monetary policy may be both deflationary and inflationary at different times. Bitcoin and Dogecoin are no different in this respect; they both use open-loop policies that lead to massive volatility. Real-world currencies use closed-loop monetary policy to consistently target a particular level of inlation/deflation, but this is too "boring" for cryptocurrency.
In reality, deflation means demand is increasing faster than supply and inflation means supply is increasing faster than demand. A cryptocurrency with open-loop monetary policy may be both deflationary and inflationary at different times. Bitcoin and Dogecoin are no different in this respect; they both use open-loop policies that lead to massive volatility. Real-world currencies use closed-loop monetary policy to consistently target a particular level of inlation/deflation, but this is too "boring" for cryptocurrency.