I wouldn't call manually exporting Java methods to the WebWidget "no effort whatsover", plus the performance hit of doing cross-language, inter-process calls, in a dynamic language while the platform languages are static.
> I wouldn't call manually exporting Java methods to the WebWidget "no effort whatsover", plus the performance hit of doing cross-language, inter-process calls, in a dynamic language while the platform languages are static.
Well like it or not JS is first class on both platforms as they both have a JS engine at the developer's disposal, Kotlin or C# aren't.
First class because there is no need to deploy your own JS engine on both these platforms, you can argue all you want, both have a webview/js engine API that are part of their respective SDK.
Yet both Android and iOS allow embedding a Javascript engine in an native application with no effort whatsoever.