IntelliJ is written in Java, but has entirely separate distributions for each supported OS. As an user of the app, why would I care if it's the same executable?

IntelliJ is written in Java, but has entirely separate distributions for each supported OS. As an user of the app, why would I care if it's the same executable? Even as a developer, cross-platform binary compatibility doesn't enter my top 10 list of important things for a programming language. Java is paying a pretty hefty price in language features (like type erasure) because things originally compiled for Java 1.2 still has to work on the Java 8 runtime. Is it really worth it?