When Goland launched it wasn't that much different from IntelliJ IDEA with the Go plugin. In the intervening years it has come to feel like a significantly better product than that combination.
I have used clion with rust plugin and while it's better than nothing, it's generally been pretty spotty on all the features, completion, marking errors, refactoring. I'm looking forward to RustRover "pulling a GoLand" by bringing a proper IDE experience to rust.
the go plugin back then was very simple. The fact that you get most of the goland experience in idea ultmate today is because they are investing into the go ecosystem as an independent profit making endeavor in and of itself, not simply a small value add.