I don't understand the past tense here, Eclipse is alive and kicking.
I recently had to choose a Java IDE to learn/use. It's pretty much a clean slate for me, as I've done only very little java in the 20-odd years that I've been developing software, and none at all over the last five years.
I comparatively looked into Eclipse, NetBeans, VSCode, and IntelliJ, and picked Eclipse.
The main drivers of my decision: Eclipse doesn't force you into any particular build system like maven (or using one at all), and doesn't force you to lay out your project folder in any particular way. This was ideal for my polyglot project, where I wanted to keep the Java component minimalistic and avoid dependency hell.
It also has a rich plugin ecosystem. With some of the other alternatives, I couldn't even use subversion, my preferred VCS, which is apparently exotic these days.
The guts of the language server behind the Java tooling most commonly used with VSCode actually come from the eclipse project, while exposing only a tiny fraction of the functionality you'd get when using eclipse directly.
It's both free as in beer and free as in freedom, and the Eclipse Foundation looks (at least to an uninformed outsider's eye) like a force for good in the Java ecosystem, fighting for what's right.
It's past tense because the situation may have changed since I last used it. It was indeed a very generically (in a good way) built product, designed to accommodate all sorts of UI customisations and project layouts. I think once IBM decided to commoditise their complement a well-meaning software architect got stuck in with a deep plugin architecture, which is very smart but in practice used to get confused a lot. Glad to hear it's better now!
Thankfully we live in a world in which we constantly start new containers with every merge to master and the orchestrator will simply restart your container if it your application gets OOM killed, so Java is finally usable :)