Well, heck even Emacs with some LLVM wrappers can do better job at C++ Intellisense than Visual Studio. Eclipse's CDT runs circles around it as well (so much for being very simplistic). And don't get me started on trying to use Intellisense on large codebases - such as Unreal Engine's source code. It is just completely unusable (30+ seconds before the completion pops up, often blocking your IDE (a total usability no-no) with a modal "Intellisense operation in progress ...").
Also anything using complex templates (= pretty much any C++ code these days) throws it for a loop - making it useless where it would be needed the most.
And don't even get me started at the ridiculous state of refactoring support for C++ - even the stupid identifier rename doesn't work reliably, and that is the only C++ refactoring feature VS has (and we had to wait until 2015 for it!).
Sorry, but that something is hard doesn't mean it can't be done - especially when there are free tools which can do it and orders of magnitude better. Even Visual Studio can do it - if you buy the Visual Assist plugin.
Even the C# tooling isn't that great - yes, it does work better (I often do combined C++/C# projects) than the C++ one, but that isn't a particularly high bar to clear. Ever tried the Java tooling in Eclipse? Heck, that editor and the various assist features almost write your code for you ...
Where Visual Studio is great is the additional tooling - integrated debugger and the various profiling functions. Eclipse can't really compete with that, even though most of the tools (gdb, gprof, etc.) exist and have a lot of features that even VS's debugger doesn't have (e.g. reverse debugging, record/replay, etc.). Sadly, the Eclipse front-end doesn't support all of them.
However, the Visual Studio's editor and the tooling associated with actually writing and managing code (i.e. the part a programmer spends most time in) is stuck straight in the late 90's - just look at how code navigation (jumping to functions, navigating between files, projects, etc.) works in the ancient Visual Studio 6 and 2015 - it is almost identical.
There is also zero integration for alternative build systems like CMake. That is important for writing cross-platform code or even just basic sanity on large projects - the Microsoft's build configuration/project/solution system with millions of settings buried in cluttered dialog boxes is just horrid and error prone, especially with their myriads of mutually incompatible options - set one option incorrectly on one library and your project starts to mysteriously crash. Good luck finding that - and then spending hours recompiling your project :( However, nothing else is really supported properly. (Yeah, I know that CMake generates VS solutions/projects, but there is no integration within VS for it - so you have to be careful how you add files, how you change build options, etc.)
The saddest thing is that many of these issues are pure usability problems where changing/correcting a stupid design decision made a long time ago would reduce the programmer's frustration by maybe 80% already - like the modal blocking Intellisense operation windows, the ergonomic disaster that are the build configuration dialogs, the decision to show compilation error with templates on the deepest template in the expansion (i.e. somewhere in the STL header) instead of where it has occurred in your code, forcing you to mentally parse several pages of error messages to find the line number or just resorting the Intellisense matches to show you the project-relevant ones first instead of the unrelated stuff from the frameworks/header files so that you don't have to dig through it. I.e. common sense stuff.
C++ isn't going anywhere on Windows, no matter what MS and C# advocates say and it is really sad that the official tooling is in such poor shape.
I could continue ranting about many other things that are regularly driving me up the wall at work (like the incredibly slow and memory hungry compiler, horrid and unreadable error messages, especially for templates, etc.), but that would be pointless. IDEs are a matter of strong preferences and opinions, but I do believe that with Visual Studio, especially their C++ tooling, Microsoft has missed the boat many moons ago. And isn't even trying to catch up as it seems - they rather focus on adding stuff like Node.js support (are any Node programmers using VS or even Windows??).