Solaris development is still going on, even if very slowly.
It was Oracle that introduced SPARC ADI, the very first sucessful use of hardware memory tagging in commercial UNIXes, which others are still followers.
Yeah, that is why Oracle still does like 80% of the work on OpenJDK, where are those contributors doing language innovation instead of repacking OpenJDK distributions?
They continued development on many of the open source and make them proprietary again them requiring forks to lots of projects. And those projects actually did continue internal development, it would be different if they just stopped all development.
And even without that they suck as a company and it sucks to be their costumer for the most part.
Even if they release something open source its often a license that prevents anybody else from doing much with it.
They are pretty much one of the worst tech companies in the world and pretty much most people agree with this.
Almost everybody other then Oracle would likely not have closed Solaris development for example.
Whoever would have ownership of Java would not just close it. Java was way to popular and would have continued development no matter where it landed.