Android will eventually adopt Swift. It is not a matter of "if" but "when". Who knows 5 year from now, you all will be coding in Swift (for servers, iOS and Android).
Interoperability of Swift with the existing APIs and JVM is not impossible, but it is a significant barrier that needs to be overcome and needs very, very significant advantages to justify that.
You could use the same arguments in the article you posted to posit that everyone will be developing on a Mac.
It's not very convincing to me.
I suppose that Kotlin outside of JVM has a similar problem to Swift outside an Apple platform. You lose a support for quite a lot of already existing libraries. Rewriting everything in Kotlin and Swift will take effort and by the time we'll get there not many will want to abandon their preferred ecosystem.