It's easy to fall into the trap of doing things the simple way or the unity way. To avoid it you have to go out of your way a bit and apply the same rigour as if you were writing your own engine.

I've never encountered a stuttering issue in any Unity game I've played.

All of the extra convenience and features afforded by using .NET are more than worth having to do a few simple things not to make the GC trigger at the wrong times. A game written by a beginner in any engine is going to have classes of errors that make it harder to keep using the same codebase over time. Compare the few simple suggestions (many of which like object reuse apply to C++ as well) in the article to the huge list of things not to do in C++.