Doesn't mean IntelliJ is bad, it's just a bit limited in that regard.
My dozens of projects are not a single project with "modules". I have a universe of code in multitudes of interrelated projects, closed source and open source. I want to refactor openly, not having to care how I'm moving code between projects. Eclipse works perfectly for this. IntelliJ does not.
Import each one individually as a new module in a root project, and everything will be hunky dory.
A "module" in this case is just an atomic closure of some sort.
I've got plenty of Intellij projects with >50 modules, each of which are their own git repository, just fine.
There are no islands. There's now switching between anything. It's just all my code and dependencies, always open and accessible and instantly available.
Creating a new project in Eclipse then requires no importing of modules on my part, I just create a new project, it's in my workspace and voila—it's now an integral part of my universe of code.
This does not match my experience at all, fwiw. I keep all manner of projects open simultaneously.
I guess that pushed them to improve ;)
As I said in a parent, I'm very certain the competition from IntelliJ got them off their asses :).
Try creating an empty project in IntelliJ and then add each of your Eclipse projects as a module to the IntelliJ empty project.