yes, like if you build things that mimic the aspect of a plane but dont fly, and you invent the name "wingableshelics" for that cathegory of objects, it still dont have sense to call a plane a particular iteration of a wingableshelics. 
Is a disservice to people that want to understand what a plane is and how it flights, the only interested in sell their wingableshelics and the narrative associated with them are the ones that build them.
Even if they will gain market popularity, sane and knowledgeable people would be pissed off and would say something like "its a plane, it flights, it works, its NOT a wingableshelics. These things are a class of useless objects built with the intention to stole money from you that have understood vaguely that some objects with wings can fly and they are selling you their shit that mimic it, scamming you". 

 The only problem that the term cryptocurrency was used at least since 1998 (Wei Dai's b-money paper). And people use crypto just as a short for cryptocurrency. 

So the category was invented way before, it included the predecessors to Bitcoin and Bitcoin itself, way before other coins joined. 

Your analogy is this completely wrong.  

 Ecash cashu or GNU taler are cryptocurrency? Are they more similar to precedent attempts to do electronic cash based on cryptography than what today is called cryptocurrency. But no, ask to chatgpt, by definition a cryptocurrency is express in function of bitcoin as a sort of clone of it that needs to have a "blockchain" and all the famcy stuffs. But not achieving what of bitcoin achieves. So they have the form of the planes, the wings and the fancy stuffs but they dont fly. But the name "wingableshelics" was used prior the inventions of the planes, from an ancient tribe to abstractly refer to prototipe of planes that actually somethimes was even able to fly for some meters. 

 It is because it's crypto money. Currency is issued by government, money emerges in the market.