It could be worse. Once upon a time a common "trick" was to avoid using foreach loops because they generated garbage. LINQ also generated garbage. I'm not sure if the .net 4.5 upgrade fixed that one.

Ultimately you wind up doing the exact same thing in C# that you'd do in C++. Aggressive pooling, pre-allocation, etc. A handful of Unity constructs generate garbage and can't be avoided. I believe enable/disabling a Unity animator component, which you'd do when pooling, is one such example.

It's all just a little extra painful because you to spend all this time avoiding something the language is built around. Trying to hit 0 GC is annoying.

It also means, somewhat ironically, is that GC makes the cost of allocation significantly higher than a C++ allocation. In C++ your going to pay a small price the moment you allocate. But you know what? That's fine! Allocate some memory, free some memory. It ain't free, but it is affordable.

In Unity generating garbage means at some random point in the future you are going to hitch and, most likely, miss a frame. And that's if you're lucky! If you're unlucky you may miss two frames.