Yeah, all of this is no longer true for java. I've worked on many jvm projects not long ago, I've never had one that would work just out of the box. You might be able to download the repo and open it, but be prepared to get reamed for a week trying to get intellij, maven/gradle, and all the other dependencies to talk to one another.
The whole point of java was to make large, dependable, and easily refactorable projects that were also highly portable. Yet at least half of the time when working with these project it's wrestling with esoteric configurations. Java cares so little about the developer experience that I don't think they even take it into consideration, unlike Go or Rust. Should I even mention the God-awful debugging? Ugh.
As for intellij, the only real use it gave me was making me hate my mouse. It's practically a running joke at this point that the amount of mouse clicks in intellij is directly proportional to your devness, haha. It's fitting because java makes even the worst, laziest developers look employable because it takes 800 lines to make a REST api, so it looks like they're doing a ton of work when in reality they're just cutting and pasting.
With the rise of containerization and languages like Go and Rust, pretty much any benefit or edge that java had is now basically gone. Java is a maintenance only language at this point and any company doing green-field dev work in java is effectively a boomer company. As long as I live I won't touch another JDBC template or Maven xml. Fuck that whole ecosystem.