Sun went bankrupt for more than just Java, it was a complete mismanagement of everything, and they only opened up Java on the last days, until Java 6 it was pretty much only a free beer thing, no source to play around.

Additionally Java has been a major success to those that played into the ecosystem, people keep forgetting there were several (some are still around) commercial implementations of Java with features not available on the free beer JDK like AOT compilation.

The way Sun managed Solaris and SPARC hardware had more impact on their wallet than Java.