Great points in this article about Kotlin. I had almost the same fears when I started learning Swift 1.0 and they all came true. As a matter of fact, Xcode just got refactoring for Swift THIS YEAR. So yeah, tooling might be behind and there’s always a slowness added to new „higher level” programming languages.
But Kotlin has been around 5 (?) years or so. The language itself is pretty solid and compared to Swift, there are already some specialists out there. The guys from Basecamp, for example, are pretty good at Kotlin as they converted their Android app to it. There are more examples of Kotlin being used successfully in production already. While everything you said is true today, I think the speed of change for this is going to be very very fast. Once Google blessed it at Google I/O, it is a matter of months before everything will get dramatically improved.
And the best thing that Kotlin brings to the table is a modern programming language. I think all of us are sick of Java java = new Java() by now… :)