There are many solid seeming ones that don't show those signs: Elixir, TypeScript, Clojure, C++, Kotlin etc. I think enumerating short lived languages is not re

There are many solid seeming ones that don't show those signs: Elixir, TypeScript, Clojure, C++, Kotlin etc. I think enumerating short lived languages is not representative since programming languages generally have very high share of short-lived/abandoned ones. But it's not necessarily a "don't go there" sign that there's a shorter average lifespan. System languages can't really go away unless the whole platform can and are doomed to be a bit clunky. Picking a language from the category that might only have a 15-year heyday is fine for a lot of apps if it's otherwise better than the system language.