JetBrains “won” because of code inspection tools and code completion that was light years ahead of Eclipse and Netbeans. I remember in my Java days I used to be able to do in a keystroke what my Eclipse friends did in a dozen dialogs.
I don't disagree, but my anecdotal experience from working with peers is that the overwhelming majority of IntelliJ users never learn a small fraction of the keyboard shortcuts and advanced tooling.
I really do believe that for most people, IntelliJ is basically a VSCode that: (1) has a better debugger and some more polish around Maven/Gradle integration, and (2) came out 10+ years sooner.
But ~10 years ago, everyone I knew was flocking over because IntelliJ felt less slow and bloated than Eclipse, and its dark mode UI was more attractive in comparison. Then it became the more-or-less official way to develop Android apps (back when Android's U.S. market share was a lot higher), and that was all she wrote.
