I know several studios local to Vancouver that are making heavy use of Go, Swift or Rust. And of course, a few that are deep into HTML5. There are games being shipped written in mruby.
I'm not in agreement with your assessment that the industry is conservative; it is largely responsible for pushing graphics into programmable pipelines, for instance, and the vendor-preffered language lock-in for consoles hasn't really been a factor since the Indie revolution took the industry by storm.
I don't take indies into consideration on my remark, consoles and mobile OS is where the money is, and none of those languages have a place there currently, with exception of Swift on iOS.
I know for a fact that teams at EA are using such tech, as are teams at Microsoft and others.
Also, thumbing your nose at Indie games is odd, considering the sales they've enjoyed and the extent to which the industry has adjusted to adapt to their surge in popularity.
I can't imagine Nintendo in the 90s treating indie devs the way it treats them today.
Swift, Kotlin, Objective-C, Java are unavoidable when doing iOS and Android development, the OS features that are exposed to C and C++ aren'tt enough for doing a game.
I'm not in agreement with your assessment that the industry is conservative; it is largely responsible for pushing graphics into programmable pipelines, for instance, and the vendor-preffered language lock-in for consoles hasn't really been a factor since the Indie revolution took the industry by storm.