The “correct” way to reduce reflection in a physical way is to increase roughness. Add a multiply node just before the roughness input and multiply anything you are using to create roughness by a scalar parameter. Value 1 means no difference, higher values means increasing the roughness you already have and the oposite will happen for lower values.
You can also play with specular values in the same way. But in this case, higher values will increase the reflections.
Maybe you’ll want to keep roughness and specular values between 0 and 1 to keep your material physically correct. To make sure of that, add a clamp node right after the multiply one I’ve told above with 1 as higher value and 0 as lower value.