I think you misinterpreted what the author aims to do. He states in the beginning that the main reason for why we don't have a good UI toolkit on the JVM is bec

I think you misinterpreted what the author aims to do. He states in the beginning that the main reason for why we don't have a good UI toolkit on the JVM is because every existing solution is bringing its own drawing library and with it their very own limitations. He advocates for a drawing library that will be supported community-wide, something like Spring is. React Hooks, SwiftUI and Flutter are modern choices that popularized the declarative approach and the author expresses its frustration that until now there was no interest in developing one for the JVM, which has all the pluses that it needs to create an ecosystem around one. Java, Kotlin, Scala and Clojure will all benefit from it. I think he is right, there is no modern graphics API on the JVM right now to do an UI toolkit or 2D/3D visualisations.