A lot of altcoins are already dead without showing it, Dash is one of them. These projects didn't really bring anything that was both innovative and useful to the cryptocurrency world. So all they had was pump and dumps. I'd say Dash had some innovative ideas but at the end of the day it didn't really have any useful utility to keep it alive. So what it experienced over the past years was some pumpers pumping it for a little while before it gets dumped again and is forgotten until the next pump, each of which are getting smaller...
I respectfully disagree with your assessment of Dash being “dead.” While it's true many altcoins have struggled to maintain relevance, Dash still has a strong use case as a digital cash system with real-world adoption. Its focus on fast, low-cost transactions and privacy remains innovative and useful, especially in regions like Venezuela, where Dash is actively used for everyday transactions. Price fluctuations are common across cryptocurrencies, but utility and adoption in solving real-world problems are what truly define a project's sustainability—and Dash still holds value in that regard.