[the_duke]

> - marketing; - big companies using it;

These are the deciding factors.

If you look at which newish languages have gotten popular over the last few years, it was Rust, Kotlin, Swift, Go and Typescript.

Building a language and ecosystem around it takes a huge amount of resources, and often tedious work that doesn't happen if people aren't paid for it.

The street cred of "hey, large company X is using it, it must be good" is also very important.

(of course Swift and Kotlin are somewhat distinct as the platform languages for Android and iOS)

[Taikonerd]

> The street cred of "hey, large company X is using it, it must be good" is also very important.

Yes, and also, "large company X is spending lots of money on it, so they aren't just going to abandon it once it's no longer the newest, coolest thing."