Kotlin is a breeze compared to Java, and it's conceptually similar to Swift (syntax, null safety, type inference etc). I love Kotlin but it's not with it's own quirks.
I would love to see a true cross-platform solution, but honestly it's a dead end in my experience. I would say C++ comes close, but I wouldn't be surprised if people feel unwelcome due to it's syntax and quirks.
I do feel more and more that cross-Platform is a illusion like you say.
As it has always been, my son. I've been hearing the wonders of cross-platform for going on three decades. Be it Unix->MS-DOS, Java on anything, or iOS->Android, there is always a compromise. Prior, it was usually that the app that didn't look native on any of the platforms. These days it seems the compromise is at dev time. But there's no free lunch. Maybe some day, but probably not within my career.
And that's fine, I now know that when the topic of cross-platform comes up to ask "what are we giving up? What will our new pain points be?" What I don't do anymore is think that this time will be different.
I would love to see a true cross-platform solution, but honestly it's a dead end in my experience. I would say C++ comes close, but I wouldn't be surprised if people feel unwelcome due to it's syntax and quirks.