It is, at least until the codebase grows so much that the IDE can no longer keep up with it.
(Or maybe it's just a problem specific to C++ projects and IDEs. The largest codebases I worked with, the ones where I hit this problem, were C++ ones.)
Yeah that can happen, though in my experience it's far more common that IDEs are broken by some janky custom build system set up by people that use Vim or Notepad++.
I think you're also right that some languages make this harder for IDEs than others. C++ is probably a worst case. Something like Java is trivial because the file structure matches the namespaces. It's probably not a coincidence that every Java IDE I've used has absolutely top class code intelligence tools.
Yeah I went from Java to JS and was surprised how much worse the code browsing experience is.
C is probably not as good as Java but I remember using Eclipse the first time with C for operating systems class, and being amazed with what a large codebase looks like and how easy it was to maneuver.
C++ contributes a lot tot his problem. IIRC you can't even reason about C++ code until you've parsed all of it. Undoubtedly, IDEs employ clever tricks and shortcuts, but even they can do only so much.
That's a mighty big assumption that someone is going to go to the trouble of setting up an IDE for a project they want to read the code of. I pull up code all the time that I have no intention of modifying just to understand how it works a bit better.
This was my though too, who cares what lines match where - when an IDE can take me to the line, and more importantly, show me the context for that line.
(Or maybe it's just a problem specific to C++ projects and IDEs. The largest codebases I worked with, the ones where I hit this problem, were C++ ones.)