For C#, there is an obvious need for a Windows machine (at least for now). But I don't see the reason why I need to have visual studio to develop C++ or Java. Especially Java, where IntelliJ is just simply better and it's available everywhere.

Xamarin Studio is good enough for Unity3d and Mono.

Why would you need VS for c++, or especially java? The both have plenty of IDE's.

What are the top IDEs for C++ and Java for macOS? Thanks.

For java you've got eclipse and intellij, probably more. I don't know about c++.

There's always emacs/vim in any case.

Emacs is s o f u c k i n g h a r d t o u s e

A high learning curve is fine for a tool you'll use the rest of your life.

It's 3 in the morning and I've been tinkering with Emacs since Noon. Is it just me or is Emacs oddly addictive?

I develop in C++ and have been happy with a combination of Qt Creator and XCode.

If you want to develop in C#, anything except msw10 renders useless, including that program.

Can you elaborate? I don't understand.