Your computer is never just running one thing. It doesn’t really matter much what one program is using at one particular moment in time. Windows is relatively smart about not maxing out too hard on ram. But if more is available, you better believe the system would use it.
More headroom means better performance in general. I’m not saying you’re going to benefit from it every moment of every day. And as I said at first, memory is not a major player in the equation. Just one of many.