Actually, Eclipse is a good thing. It is not perfect. But it gets the job done. Most people don’t get the most out of their IDE and for them, Eclipse or Netbeans is good enough. I personally cannot justify paying for an IDE and i would need to to get the functionality out of IntelliJ. My guess is that the comment about Eclipse is a jab at Java. Honestly, i have done this for a long time with alot of languages (COBOL, VB, C#, Java, Groovy and a lot more). What really matters now-a-days is frameworks.
As for considering Kotlin, I have. But for my personal projects. For at least to learn. But most teams struggle enough with everything else. Switching to Kotlin just does not add enough value. Yet. The good news is that it has something in common with TypeScript. And I don’t see the typical corporate dev teams switching. :(