One might actually suffer from GC overhead much more than that, i.e. it might be the number one thing to be aware of and optimize, especially if your program has millions of pointers and/or a large heap.
Yes, these days, GC might easily be the biggest problem to the point that focusing on anything else would be a waste of time and premature optimization.
GC pauses can be anywhere between 300ms to 30 seconds or more when it starts becoming an issue.