Additionally Kotlin also targets native. `suspend` in Kotlin was very much designed with this in mind as it's easier to implement than something that requires an extensive runtime like Loom.
Kotlin will still support Loom on JVM and there will likely be integration with suspend/flows etc also.
That's a good point. Generally, I opt for languages that either compile away their nicities to avoid runtime hits, such as Rust being compiled to WASM, or languages that bring nicities in runtimes that they _completely own_, such as Java on the JVM.
The problem with Kotlin and the like is that they can't easily compile away their features due to inherent runtime dependencies, e.g. garbage collection, making them poorly suited to environments with a very minimal runtime like WASM, while also being at the mercy of the host language creating runtime abstractions that have mismatches with their own language's features.
Although it'd be unfair for me to say the JVM is designed only for Java; invokedynamic and non-reified generics both assist JVM targetting for non-Java languages such as Clojure.
