Platform languages might not be so shinny as guest languages, but they will stay relevant as long as the platform plays a major role, and might even outgrown the platform into other domains.
Guest languages are always fighting for adopting, require FFI, additional debugging tools, tend to create duplicate libraries for everything ('cause their use must be idiomatic in guest language).
Even when FFI is kind of copy-paste compatible with the platform language, eventually the platform language will introduce concepts that aren't that easy to integrate into guest language, or the shiny features from guest language require funnel interfaces to the host language, or aren't exposed at all, thus increasing the divergence.
Then comes the rebranding, which might introduce uncertainty into the ecosystem regarding its future.
So coming back to the platform languages.
C, JavaScript, Java, C#, PHP, Objective-C, Swift might be not be the best, and they have their warts (how I love to hate C), but at the end of the day they own the platform that made them what they are, and will stay around as long as their platforms are relevant.
Guest languages are always fighting for adopting, require FFI, additional debugging tools, tend to create duplicate libraries for everything ('cause their use must be idiomatic in guest language).
Even when FFI is kind of copy-paste compatible with the platform language, eventually the platform language will introduce concepts that aren't that easy to integrate into guest language, or the shiny features from guest language require funnel interfaces to the host language, or aren't exposed at all, thus increasing the divergence.
Then comes the rebranding, which might introduce uncertainty into the ecosystem regarding its future.
So coming back to the platform languages.
C, JavaScript, Java, C#, PHP, Objective-C, Swift might be not be the best, and they have their warts (how I love to hate C), but at the end of the day they own the platform that made them what they are, and will stay around as long as their platforms are relevant.